I'm told the Schneider 90/5.6 APO is 'better' but I have no expereience with it and can't comment. In any case these lenses are much cheaper now then when they where new. I paid almost $1000 (new) for my APO-Rodagon-N about 12 years ago!
I'm guessing, but I think you should be able to get one for $2-400 now, but I've not really looked. Maybe $20 bucks at a flea market if you are lucky!
Of course I've used it in the darkroom too. It is a fine lens but I found that I needed to stop it down to about F8 to get the best out of it. It may have been better at F11 but I rarely used it that way due to the long exposure times in my case.