If you want to bet on CS:GO/Dota2 lounge I'd firstly advise you to get into the competitive scene and watch a lot of matches via streams and similar. Get to know the selected teams' tactics so you don't really have to look at the win % which the site posts. For instance, I've been busy in the past few days and I wanted to bet on 8 different teams on dota2lounge from which all 8 had a win % of 25% or lower. I was right on all of them, but kept forgetting to place a bet. As I've said, you need to get to know how a team plays and how much of a counter-play it will be to the other team (thus providing your own win %).
Oh, and my final advice would be, don't bet... Give the items to me. I'll make a profit out of 'em... Tee hee.
Sincerely,
-cHeT [BeWasted]