ball and trunion to a splined output

I picked up a trunion style abody trans and was told that I would have been better off to get a later style slip yoke tranny for my 68 barracuda. my question is does the erlier A-body 4spd have any advantages over the slip yoke type(gear ratio or other) and would I be better off selling this to someone looking to do a 66 or erlier conversion or replacement. I gave 250.00 for the tranny and hope I did'nt make a bad buy.