reohn2 wrote:There's no advantage in an eccentric BB over chaintugs the amount of adjustment is about the same or or more for the c/tugs.
The argued pros and cons are -
moving the wheel has an effect on other fitting (brakes and mudguards)
moving the BB effects the geometry
There's no agreement among framebuilders, I've heard strong opinion on both.
Of the two I've only used EBBs, pinch bolt type and the set screw ones, both are pretty crude but have worked faultlessly for me. The wedge type is the one that is prone to getting stuck, but from what I've read it's usually down to lack of maintenance.
I don't know how much of an issue moving the wheel is, but I think the ideal would be sliding dropouts which also act as a torque arm with the right hub, an advantage is a disc brake would move with the wheel. They also make for a versatile frame, a change of plates allows for a change of gearing.
http://www.ahrensbicycles.com/Sliding-Dropouts.htm
I had a quote a couple of years ago to have these fitted to an existing frame; dropouts, cable guides and powder coat was around £250, not cheap but if it turned a frame you liked into one that met all your criteria not extortionate either.