BFL: if you have a BFL Single, an early FPGA MiniRig (cgminer has a parameter for later ones to fix them, check its documentation) or a BFL SC (ASIC) don't waste their hashrate on P2Pool, they have huge latencies and can't perform well on P2Pool. Put them on a traditional pool.
Are you sure, or are you just going off the FUD on these forums? Clearly the FPGA products have an issue, but these guys claim the ASICs blow through an entire nonce range in a few ms:
https://forums.butterflylabs.com/jalapeno-single-sc-support/3367-reducing-20%25-hash-rate-penalty-using-bfl-hardware-p2pool.html#post42224It would be a pity if the p2pool guide was turning away major hashpower unnecessarily. In fact, looking above the linked post, there is the exact quote from above used to justify not participating in p2pool.