I'm not after comments about these individual bags 2 bags but rather those regarding their comparative suitability for spring and autumn scottish conditions. Night temperatures can vary beteen -5 to +8 but there appears to be a lot of ratings difference between these 2 bags. The hydrogen is ideal for temperatures down to zero (-1 rating) and the helium (-9 rating) is better suited for those spring scottish nights when it dips a bit below.

There's only 220g difference between the two. Is it better to err on the warm side or cold side ? Given that I can only carry one bag I'm concerned that if turns out a bit warmer, say 5 - 8 c, then the helium will be too warm but then I suppose to be too warm is uncomfortable whereas being too cold can be dangerous.

stating the obvious, but ...

if it's too warm, you can always unzip. It's bit harder to deal with too cold.

I've just come back from the TGO Scotland crossing this May when it was supposed to be the coldest May for 25 years!

(Doing a mainly high level crossing, BTW.)

I was using the Hydrogen and it was sub zero every night bar one. I needed to be fully dressed for every night and although I wasn't shivering at any stage I would have prefered a warmer bag.

Peewiglet also used the same bag. Er type .. not mine .. but on a lower route and I think she said she was warm enough for most nights, but had put on extra at times.

The price difference between the two is fairly steep if I remember correctly. Personally I prefer a bag with a neck baffle and the Hydrogen doesn't have one. I would have been much warmer had it.

It all depends on how big that 'dip' in temp is and how 'hot' you are at night baby!

Best of luck.

Thanks for the comments - there only seems to be £30 between the two so I think I'll go for the helium (or should I try PHD or RAB hmmmmmmmm decisions,decisions !)

Ecco

I have a Helium and it is great. My sis has an equivalent PHD and overall there are not a lot of differences - I know I would be happy with either.

If you are worried about temperature, I think that you can get a version of the Helium which has a long zip to allow a bit of extra ventilation (the Heloum EQ). It does cost more wonga though. Best price I have found for these bags is on the Outdoor Shop website where they seem to have a semi permement £50 discount.

Hi ecco,

As Bob said, I have the Helium. I think you need to take a/c of whether you tend to be a warm or cold sleeper. I'm pretty skinny and so I get cold. I was cold in a baselayer in my Helium in the Lakes on the first below freezing weekend last winter, but when I put on my pants and a fleecy hat I was comfy for the rest of the night.

I think a cold sleeper (like me) could be cold in the Helium if it got *very* chilly out. On the other hand, I'll happily sleep in my pants, hat and primaloft jacket if necessary, and I think that would keep me warm most of the time. I'll generally take the Helium, then, as it's smaller than my warmer RAB.

I hope this is helpful but suspect it may not be. Ultimately it depends on how warm you sleep, and how keen you are to save weight/bulk.

Good luck :)

Bob, Thanks for the comments - I've been watching your TGO exploits through the forums closely. It was a great way to do it. It's something I always want to try - bivvying on top of a munro. However, I'm always afraid that when I try it, it'll be tipping down with rain. Still it's on the "to do" list and the rab survival bag looks great.

Duncan, Had a look at the EQ - good idea but the outer & zip adds a lot of weight (relatively). If it's a choice of being occaisionally too hot versus too cold then I'll chose the former.

Peewiglet, thanks for the comments re the helium - I thk I also sleep on the cold side so it's good to know you still feel a little cold in the helium.

Ecco - I sleep cold and I have used the Helium all year round and NOT felt cold once. I have the zip partially undone once I've warmed up as well.
Maybe down suits me?

JJ - Have you ever found the half zip a pain - perhaps on warmer nights when it would be nice to open the bag out and use it more as a duvet ?

No. If it gets really hot I just open the zip right up and lay it over me like a strangely-shaped duvet (me still in the silk maggot-shaped liner).

The down is such a natural material that it's warm when it's cold outside and vice-versa.

I'm geting confused here. The Hydrogen is the -1 and the Helium is the -9 bag correct?

No wonder you weren't that cold in Scotland then Shirl if you had the warmer bag? I wish I had paid the extra just for the comfort factor, but still maintaining the weight benefits.

BTW I've notice mine is starting to lose a small amount of down through the stitching. I suppose you have to allow a certain amount of 'seepage', as all my other bags have done it, but Marmot claim that the bag is 'down leakproof'. I suppose I'll send it back just before the warranty is up for a check!

Thanks ecco for the comments re bivvying. Since reading Ray Jardines book 'Beyond Backpacking' and Ronald Turnbulls 'The Book of the Bivvy' I wanted to try it for more than just one night. So the TGO trip this year was a bit of a baptism of fire!

I'm hoping to compile a collection of diaries this year from a dozen or people who did the Challenge and publish a booklet or pdf booklet, so that other nutters like us can pour over the experiences, comments on gear etc. I'll let everyone know on OM when it is ready.

All I can say is try it. I've still yet to give the Rab bag a good soaking to see if it leaks. The guys at Rab say it is made from Pertex 6 whatever that is and it is waterproof.

In fact I'm off with my wife tonight to the Brecons and she is trying out the Force Ten Bivvy and I'm using the Kathmandu Trekking one. The F10 has in built bug netting which she may need and the KT is just a tube style.

Honestly what are we like? Normal people just go to the pictures!

If these bags are down I find that I can use a down bag happily in temps much warmer than it is designed for with out over heating where as synthetic I will easily over heat and get sticky.I think down seams to self regulate. I have found the same with feather duvets.

My Down bag is rated 0 to minus 25 and I am comfortable in it in all but hot summer nights, you know the ones I mean.

JJ - Thanks - helium here i come !

Bob - correct on marmot ratings. I've read elsewhere that the marmot do "moult" a little - i suppose thats whats happens with such a light lining. Its quite easy though to pull the down back through from the other side - search OM & UKC

Great idea for the diaries - inspiration for us all ! Look forward to them. Peewiglets account of the TGO is excellent.

Oops - thanks Bob for pointing out my cockup! I've got the lighter one - the Hydrogen - not the Helium.

That explains JJ's remarks. I was very surprised indeed to read that JJ had never been chilly in the Helium. Now I can see why!

(fx: trots away, blushing...)

Hi,Dont worry about confusing the Helium with the Hydrogen.It appears that TRAIL magazine have done exactly the same.In the July 2005 issue on page 27,there is a comment about the minimum temperature for the Helium being only-1 degree c.As Bob says Helium is -9 & Hydrogen is -1.Trail quote weight of the bag as 595g which is the weight of the Hydrogen so looks like they are in fact referring to Hydrogen Bag but have named it as Helium in error.

Oh dear Oh dear me....
Not again....
That's the sales of heliums going down now