I am so glad you decided to take the plunge as it may be kinder to your shoulders.
I don't have room for anything but a Juki with a 9" throat and a babyloc Jane. So far I am still able to quilt on either one of them. I get up every so often and move my shoulders and arms around to loosen the muscles up. I usually quilt about 5 - 6 hours at a time. I do take a few short breaks.