As a toddler and baby I wore some kind of brace to correct hip alignment, and then my first couple years of school I wore corrective shoes. Fast forward 30 years and I have pretty much worn shoes and boots "as is" since. Snowboard boots have always hurt. I naturally pronate alot and have relatively very flat wide 9-9.5s.
Last year I got these Medics at this exact time (order history says 9/18/12). Got a new pair last week. For sizing, the boots are 32 Lashed(blue) and Tm-Two, size 9, the shoes are Keen size 10. Both pairs of Medics are 9-9.5. They are considerably thicker than a stock insole, especially in the footbed, something to consider in terms of volume, but they seem to put things in the right places for me and everything just fit better.
These bad boys spent 100 days on the hill between 2 pairs of boots; and after drying in the car on the way to work after I would wear them in my work/hiking shoes.
There are several key factors that have made my feet super happy this year. They correct my pronation. There is a ton of padding for landings and the concrete floor I stand on at work. Even though I have pretty flat feet the arch support provides significant comfort and really positions my foot correctly in a tight boot for a performance fit.
Here are some photos to compare how they have broken down and molded compared to a brand new pair. You can see my flat arch put creases in that arch and will probably benefit from the new pair. The padding looks like it has not packed out one bit, Blue Magic's claims (no pack out) seem to hold true. This first pic here is the new ones.
Overall, I'm stoked. Despite their awesome performance I would definitely describe this as an endurance test and would suggest keeping 2-3 pairs around.