It seems that there is a divide on which direction P2P will take. We have the old fork still running that will not be compatible when segwit is implemented around August 23rd, true? Then the the 1Meg or lowmem version that would be the correct version for segwit, true? Then we have segwit 2 which will be an alt coin.
"1Meg"+segwit requires 2x which will be an altcoin. "1Meg"+segwit is based on my PR against the main p2pool repo so when it will be merged that will be the correct version for bitcoin.