How to Find the Perfect Running Shoes
How do you know if you have enough arch support? The best way to make sure you have enough arch support is to go to a store that can provide a gate analysis. What they are looking for during a gate analysis is how much your arch collapses and whether or not you overpronate (your feet roll towards the inside). You know your arch has enough support when the foot is balanced over the center of the shoe and not visibly overpronating.
Best cushion for marathon training? I would not recommend a specific shoe. There is no such thing as the "best" shoe for marathon training, or any other kind of training. Every runner's body is different and as a result, we all have a personal preference about which shoe is the best shoe for us. The most important thing is to make sure your shoe is the right shoe for your biomechanical needs and for the experience you are looking for during your run.
How often should you change your shoes? Traditional core shoes 400-500 miles, PureProject 200-300 miles
Type of socks to wear? Make sure you wear a performance sock made of technical fabrics that wick moisture.
Is too much cushion ever a bad thing? The amount of cushioning a runner prefers in their shoes is really a personal preference. Even within our neutral line, we have the Glycerin 10 which is our plushest, most cushioned shoe in our line and the Ghost 5, which is also a neutral shoe but offers a different ride to the runner.
What is the difference between road/trail shoes? Trail shoes have an enhanced outsole with a more rugged lug pattern that makes it easier to grip dirt, mud, etc. Also some trail shoes offer different types of protection from rocks and uneven terrain like Cascadia 7 which has a Ballistic Rock Shield and Pivot Posts.