I've watched with interest since starting this thread. I've subsequently bought the Anquet OS 25K HD package and upgraded to the latest version of OMN. I'm more than pleased with both. As I walk across the UK, I feel that I'll get VFM from my purchase as this will aid planning and navigation when out & about.
You will see from these links that both Anguet and Memory Map are now offering the whole of the UK at 1:25,000 for around £350. I already have Anquet maps for the UK at 1:50,000 and 3 National Parks at 1:25,000 but I'm considering upgrading to one of the new 1:25,000 packages. I'll be running it one both my Samsung Galaxy Note and Samsung Galaxy Tab 2 7.0. Anquet works well on both devices but storage is limited. Does anyone have any views on whether Memory Map is better than Anquet and how I might manage the maps files on my Android devices?
Your idea of using an iPad Mini as an outdoor navigation tool seems fine, if a little costly. Unless you have a spare iPad Mini lying around, there is the purchase price of around ¬£269 plus the GLO at ¬£90 and the Lifeproof case at ¬£62 ($99). A total of about ¬£430.
I run Anquet on my Samsung Galaxy Tab 2 7.0 and it is protected by an Aquapac medium Whanganui case. This combination produces similar results at a lower cost.
Most Tablets now have built-in GPS and for anyone starting from scratch then the Tesco Hudl at ¬£119 with an Aquapac case at ¬£25 (total ¬£144) seems a more affordable hardware option. All of these assume that one already has access to the mapping software.