999 miles on a Delta Connection CRJ-200 from GSO to DFW in September 2004. This was right when the DFW pulldown was happening, and it was on 9/11, so not a whole lot of traffic on a Saturday morning (13 people on the CRJ). I took the exit row and spread it and relaxed.

Done MHT-ATL plenty of times on full flights. CRJ-700s are tolerable in 2 C/D or Row 14; otherwise I'd rather not...