Hey IamDavid:
I have WinRAR 2.71 and it will decompress/view Ace files (or they are on the list, I don't have anything to test it with at the moment). Maybe you just don't have the newest version?
It can only compress to .RAR and .Zip, but that's all you really need. RAR is an excellent archive type, and Zip in universally compatible.
If you are interested, 2.71 can decompress/view: RAR, ZIP, CAB, ARJ, LZH, ACE, TAR, GZip, UUE
(Ok...so 15 was a bit of an exageration...but ARJ, LZH, ACE, even the unix formats, and the CAB ms files)