Strengths: I have not found any problems with grip on very muddy/clay ground.
Weaknesses: When I used them on frozen ground on 25 mile run I got blisters on my arches. This is something other than the shoes, e.g. socks, not being carefull enough with putting then on i.e. making sure there was no grit in them first.
Overall: I am pleased with the traction in slippery conditions, my 'poor' rating for comfort might be unfair.