You should check out Proxy FireWall from uniqueinternetservices.c0m
Thier SOCKS proxies work pretty well, but you said you were going to use with bots- it might be a little over saturated if you're going to use on social networks but for anything else it should work pretty well.

I also like Elite Proxy Switcher. Their proxies aren't great, but they do have ALOT of them and the software is pretty clean.

Hope this helps..