One of the best 50 seaters was the Nihon YS-11, and it wasn't that long ago when Piedmont first purchased them for $1M apiece, and was flying them off of shale runways. It was fast, and quiet inside (not out) and had ample room, we had a bunch at PBA in the 80's. "It cost as much to run a 50 seater as it does a 733"? Guess again, the DOC's on the 733 are double that of the RJ, right down to the landing fee schedule at MAssport. Obviously you don't flight plan your RJ for 5000#/hr burn, plus there are two more salaries in back of the 733, and two higher salaries up front. Not certain about Boeing leases, however Jet Blue 320's will cost you $375,000/mo.