Randy, I have been running WS2012 and AO on dual pcs running JRIver/Jplay for the past year now. I am one of Phil's alpha testers for AO, and his work to get WS2012 to sound great is nothing short of genius. It is now so easy to use, as well (no need to be in a certain directory, etc, etc) that it makes using core mode on WS2012 quite simple (audiopc is core mode, controlpc is GUI mode).
Sorry in advance for the super long post, but contemplating changing your computer OS is not a small matter. I'll share my experience.
I'd like to second ted_b's comments. After reading several very enthusiastic accounts of the improved sound quality people were getting from WS2012 and Audiophile Optimizer, I wanted to hear it for myself. I was particularly interested because I was very pleased with the sound I was getting from Win 7/8.
I had all of the concerns I've read expressed here, from whether everything would function properly, how usable it would be and being able to safely and easily go back to my (then) current system if I wanted to.
I was fortunate in that I had an older computer that I wasn't using, so I installed the free trials of WS2012 + JRiver on it. Even with no enhancements to the computer and running WS2012 with its full GUI and with no AO, the sound was better than I'd ever heard before. The difference wasn't huge but it was evident. That was in line with what I'd been led to expect. From what I'd read, the biggest gain would come from AO. Also, I had no functional issues.
Based on that experience, I decided to go all in... or at least "all in" for me. Others go a lot further with their optimizations. Dual Core i7, AO optimized WS2012 8GB RAM SSD servers, both in Core mode, connected with JPlay (software), with a Paul Pang Audio USB Card in the audiopc. The improvement in sound quality was incredible. I was introduced to a world of musicality that I had no idea that the (flac ripped) CD's I've owned for all of these years contained. The best thing I can say about the AO is that it absolutely lives up to the claims made by its developer, audioPhil, as well as the many users who praised it.
If you decide to give WS2012/AO a try, I can say from experience that switching to a new OS can seem very unfamiliar and somewhat intimidating at first glance. However, audioPhil has written very direct and clear instructions for the entire process and following them carefully will lead to success. In hindsight, having done the operation a few times now, the whole thing can be done very quickly (less than 30 mins, including installing WS2012!!) once it's all familiar and you don't feel any apprehension about making a wrong turn. It's very easy to use as well.
It's a path for people who really want the best in sound quality, so it's a good idea to dedicate the WS2012 computer(s) to just audio, IMO. I have another computer in my system that runs Win 8 that I use for video, internet and other general purpose multimedia. That way, I didn't have to give up the versatility of a consumer OS. All of these servers are small, quiet and modestly priced. Others may (strongly) disagree, but I haven't found the return on investment of big dollars into the computer hardware
to be worth my while.
A previous post in this thread recommended CloneZilla for back up. I strongly agree. It's free and has worked efficiently and flawlessly for me. I've been able to back up and restore my OS drive as needed, which has made the whole process a lot more comfortable.
So to sum it up and to address the OP's question, WS2012/AO is entirely worthwhile, to put it mildly. I feel that I have an advantage over any system that doesn't have it (and that includes most every other system), no matter how advanced or expensive it may be.