I am 6'3 and my wife is almost 6' and we just got a KHS Roma this past summer. I ordered the large frame size and it fits us both fine. My seatpost is out quite a ways but not to the limit line.
The wife has plenty of travel left in hers too so it could accomodate an even taller rider. Yes the frame is a bit smaller that the "half bike" that I ride by myself but not by much and the most important thing is that the bike is really comfortable. I can ride it all day. It is very adjustable too, you can fit it just the way you like. Check out their website at I think KHSbikes.com If that is wrong just do a google on KHS bikes and it will come up.