Two potential problems with Hokas: They are wide and can twist your feet on frozen churned up mud. Secondly how well do they grip on ice?
Somehow I doubt we will get the same conditions as in 2014 where soft bog was good for Hokas.
Anyone just reading the 2014 blogs will have got only one version of the race. Compared with 2013 ,2014 was tropical ! It never got cold or really windy
. To some extent you need to save your final Kit choices until the last moment. I suspect that some of the 2014 Challanger finishers could be in for a shock if we get snow and ice like the first two years.
If you do go for Hokas then put a pair of conventional shoes in your drop bag.
Been back reading the forum. Re packs: you probably need about 30l + front pouch.
I used the OMM 32l for years but its a bit to long in the back and so rubs the top of my lower back after about 20 hrs. The raidlight Runner 30l has a pad system that prevents chaffing of your back. Used it in 2013 and 2014 with no sore spots at all. The main down side is that it is built so light that it wears out. The waist belt was held together with cable ties when I finished. ( It had done several MM,s and other ultras.)
Bogs are not avoidable. You just have to get to like them.
As far as sleeping systems are concerned you need to think layering. Go for a serious bag liner and a fairly good bag rather than a super expensive bag . Don,t ignore the mat . The Thermorest Neoair mats are great as they pack so small. Roll mats are a pain in the ass is you get jammed in the small wall gates and they are more difficult to keep dry.