Im not convinced they would get 5HP or anything near that. What I do think is removing the screen WILL increase throttle response and make a small gain in power, but probably too small to measure on a dyno accurately. I dont care for more power my 450 has plently but if I can gain some extra response then Im all for that. The screen may be less of a restriction than the filter itself but it still IS a restriction and would affect the air flow. So, removing the screen combined with a much thinner and free-er flowing filter than standard would help even more I would say.