I have flat feet as well. The surfaces I run on will vary, but primarily a treadmill, grass, and HS school track (rubberized or gravel/fill). Some ashphalt and pavement as well, perhaps. My impression is also that New Balance is a great brand for runners. Since I'm still getting used to running, I have the usual lower leg pains (specifically in the shins). Right now I have an ok pair of Asics with some Scholl's inserts (just added them). I think I'll wait for my legs to feel completely fresh and then get back it. Hopefully the majority of these pains are part of the adjustment process, and will go away on their own. Maybe the shoes I have now are good enough, but only time will tell. Even if I got a great pair of shoes right now, it wouldn't matter unless I rest my legs properly.
Thanks for the responses thus far.