rapogee,
Yes, you can try any re generator or conditioner with your Spectral equipment. As in all things audio, sometimes they are an improvement, sometimes not. Will not hurt to try.
Being a Spectral owner for 20 years, I tried a lot of different things. When I could afford MIT ICs, SCs, PCs, power conditioners; they always made a difference for the better over the other stuff. Spectral and MIT are made to work together. That's the "rub". When you go for a Spectral system, you are locked into their system approach for the best SQ from their equipment. Mix & Match is a crap shoot. Spectral does not always play well with "Others".
Joe Abrams and Scott @matrixdude @verison.net have both been a pleasure to deal with. Also, keep a look-out on the used equipment sites to find deals on used MIT stuff. It may take awhile,but you will find what you need at decent prices.
I switched to Pass Lab in 2016, Good Luck finding what you need.