How can you say that the filter doesn't need changing at 8000 miles?????????At 8000 miles the filter should not require changing. About the only thing an aftermarket filter will do is lighten your wallet, its tuff to beat the OEM filter.. save yer $$ for track days..
The aftermarket filter manuals say that the filter performs better when "dirty".I take it,comeback you think it should be changed aready...dunno really. It's not as dusty or warm here in Ireland,maybe it will do a while?