I have never used Edge but isn't Street Smart Pro their day trading app? It is based on the old Cyber Trader, which was a premier daytrading platform. As to Schwab they are a good firm but there are better choices for pure daytrading.
It was a while ago now, but I used Schwab as my initial broker, also had scottrade for a while. Street Smart Pro was definitely one of the worst platforms I encountered. Definitely below scottrade, which wasn't good as well. Maybe for order execution it's ok, but it looked like something out of 1995. I used street smart edge as well for a while. It's certainly much more advanced than street smart pro. I don't feel it's nearly as good as a platform like thinkorswim, but it's at least a good step above street smart pro.
StreetSmart Edge is total garbage. Useless tools, memory leaks, and clearly built by B team traders/programers. The SSPro app was fine, but they puuled the plug on it.