My old running shoes are a pair of Nikes that are supposed to correct my type of pronation. I'm not an expert. But I researched a lot about it. I also read a lot about the injury I suffered last year so I knew what I needed.
Anyway, the first thing he did was measure my feet. Then look at my calves and ankles as I walked around the store barefoot. Of course I rolled up my pants first. He wanted to see if my calves and ankles did anything out of the ordinary. But I was fine.
I also remembered to bring the socks that I run in and tried on my first pair, which were the Mizunos. If you forget this step they have tons of socks you can use. From there I tried on a pair of Asics and then a pair of Nikes. The Nikes are like the ones I have now but the updated version.
Nikes are nice because they have that foam that makes it feel like you are running on pillows. However, I wanted to try something new. So that's why I picked the Mizunos. They are also narrower and sturdier around the ankle. It is taking some getting used to.
In each pair of shoes Mike took me outside to watch me run. My ankle, according to Mike, tends to rotate just a tad when I run. But I looked good in each pair.
I also tried them on with some amazing orthopedic inserts. This was to correct the slight ankle rotation. At that time I didn't think it was absolutely necessary to get them but maybe if I feel like splurging one day. (They cost $40 a pair but last for 3 pairs or running shoes).
So basically the choice was down to what I wanted because any of the shoes could work. The Mizunos were the more expensive pair (the Nikes the cheapest). It's always good to try out different brands of shoes so I figured this was the perfect time.
Right now I'm trying to break them. I've run on them twice already. Once during a long run of 16 miles and the second time during interval training on the treadmill. Tomorrow I'll do a short run of about 3-4 miles or so to further break them in. Then I have a long run on Sunday.
I say definitely try to find a professional running shoe retailer where you live. Not just any place, a place where they can actually fit you for a shoe. It is so worth it.