kpug, why not just measure the saddle heel to brake hood distance on a bike whose upper body fit you like, and compare that measurement to the RB2? You'll find out quick if the fit issue can be fixed with a nice-looking stem.

The one you have looks sort of like a 11 cm, and on that bike I think anything down to an 8 cm would look good. That 3 cm leeway gives you a lot of effective adjustment, to see if it can get comfortable.

Top tube can be a bit misleading. If you set your saddle the way you did on every bike, by setback and knee angle, the saddle position with respect to BB will always be the same regardless of seat tube angle (assuming you can always get a seatpost that works right. The correct top tube will be longer for a laid back seat tube than for a steeper one. I THINK the RB's had more laid back seat posts, but I could be wrong.

Anyway, this "real-world total reach" measurement will tell you if this can work with a shorter stem, now that you have the saddle nailed in.