If the bypass valves were well made, Id be all for em, but I have heard too many stories of those things falling apart, and you dont want that pieces of that loged in your throttle body keeping it open. Till then I say dont drive in water thats deep enough to submerge your filter; bypass valve or not, its still not good.
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Just call me.............Mr Hyde
03 Topaz Blue 540i M-Sport
The TL-S / The 540i