After buying a second hand SL3 and nest last week I've just got my first opportunity to put it up in the garden ahead of next weeks camp, and I like it (so does her indoors).
The head space is perfect, the floor space is excellent and at first glance it seems fairly stable. It's the older model with 2 vents and a 1 way zip but that doesn't bother me too much.
I bought this purely for car camping trips, better weather wildcamping and we're hoping to do the Cumbria way next year so this would come in very handy. Got a Hilleberg Nallo 2 for wilder weather.
I think at some point I'll be hoping to get some walking poles and trying to errect the nest with those, I also wouldn't mind a full or 3/4 solid inner at some point. I've read the first 10 pages of this thread and will read the rest another day but for now, I'm just looking forward to getting it up in the hills 