Last week was 7hrs (90km), i'd say 4 and half hrs per week is average for me. Ideally I'd be hitting 100km per week if time allowed!
Whilst training for a marathon is definitely difficult and requires time, I still think there is a relative aspect to it depending on your current running ability/ general fitness and your target marathon time.
I'd highly recommend Adidas Evo SL. But again, i'd say this depends on the runner. I have a friend who is 6' 3" and a bit slower than me, and he says the Evo SL is the least stable shoe he has ever tried on.
Asics have just brought out a new range - sonicblast and megablast - to go alongside the novablast and superblast. I use the Novablast as my everyday runner. Superblasts (I have not used) come highly recommended but are pricey! The two newer designs also look good, but again not used these.
I plan to buy/use Adidas Adios Pro 4 for the marathon.