There are two places in the Denver/Aurora area I can think of that are Subaru specific and that won't rip you off (personal businesses aside...) Suba is fantastic. They know what they're doing but they're always pressed for time. If you can leave your transmission there, I have no doubt you come back to something awesome.
Otherwise, off of Hampden and Tower, in Aurora, there is a place called "Speedy Roo" and they do great work for a very competitive price. Their staff is knowledgeable and do seem to genuinely care about the Scoober. Even the older dudes there are into scoober rallies and such. Fun people for sure. Please, let us know where you take it and the results (price/enthusiasm/knowledge/etc... of said place...)
I love Suba! If they weren't always so busy, I'd be there all the time!