do not use a foam filter.....they suck once you start putting miles on the engine.....engine heat makes them dry rott and then they start to chunk.
the apexi seems like filter most people use...i have a blitz sus.....its alot more free flowing than the apexi but it comes at the cost of filtration....not that it will let bugs in or anything...i got it because it is stainles steel and i can get it alot cleaner when i need to when comparing it to a cotton gauze filter.