I'm might be moving abroad again and am thinking about buying a bike and trainer to have with me and leave my current bikes (including tri and road) in my house in the states (so when I'm back here, I can train).

I currently ride a 2008 Cervelo P2 in 56 that fits me very well. I also ride a 2007 Raleigh Supercourse road bike in 57. Gravel bike is a 57 (Raleigh RX) and mountain bike is roughly a 19". I'm 6'1" and wear 32 inseam pants.

I'm thinking about either buying a Kestral Talon X as a road bike and putting aerobars on it. The other option would be a Fuji Norcom Straight. In either case, I'm trying to figure out sizing.

I can certainly ship one of my current bikes. If I did go down the extra bike route, what do you guys recommend on sizing (assuming I purchased from Nashbar or Performance and don't have a chance to test fit)?

Top tube, stack and reach are below (one note, is that the Cervelo measurements are based on using the forward seat post position, Kestrel also has a forward seat post position but the measurements below are in the rear seat post position).

Cervelo - 56 top tube 545 Stack 531 Reach 429
Kestrel Talon - 55 top tube 555 Stack 548 Reach 395
Fuji Norcom Straight - 53 top tube 527 Stack 503 Reach 420
Fuji Norcom Straight - 55 top tube 550 Stack 540 Reach 435