i agree with walrex, screwb. you said that koth (and i assume by extension, "bad maps") would "give you a disadvantage" but you fail to realize that basically your entire team is a bunch of open players who came to IM to save it. watching a 30 minute demo of an invite team playing propaganda instead of another episode of whichever anime you're watching right now will give you a greater edge against a team that may barely be better than you. the worst excuse you can make about losing to a team is that "this map is bad" when in reality the team you just lost to likely has much more experience on whichever map they just beat you on
in short, practice your bad maps and you could beat a team that beats you 5-4 on <popular map>