with mssfix 1400, 20MB/sec was stable. A few errors but no loss of connection.
22MB/sec gave a couple of errors but did not disconnect me
Authenticate/Decrypt packet error: bad packet ID (may be a replay): [ #10253565 ] – see the man page entry for --no-replay and --replay-window for more info or silence this warning with --mute-replay-warnings
24MB/sec started to spam errors and I lowered speed before it broke.
I guess it must just be latancy related when at high speeds over UDP, but my connection to the server and ping are solid outside of the tunnel from what I can tell.
Solved by… cheated really
Anyway, switched to TCP and reached 36MB/sec which isn't to far from my max without VPN.
The other issue with the routing table and the pppoe connection that shouldnt of been caused by openvpn failing shouldnt happen now as openvpn is stable.