There are a lot of happy GS112 users out there. It captures a certain tone that many bass players strive for. However, my personal preference is for a more uncolored, midrange-articulate cab. To each their own, of course. Believe it or not, there is a ton of variety in how the various 1x12's sound. To my ears, the variety of offerings in modern 1x12's are much more distinct and individual sounding than, say, the variety of 4x10's that you used to see 5-6 years ago. I have not heard the EA CxL-112 (shocking, I know!) or the Accugroove Tri 112L, but from what I know of the rest of the gear made by these two companies, those two would likely vie for my top honors in the "1x12" category (even though the Accugroove has a total of 3 drivers).
I prefer cabs with an accurate, uncolored sound, with good balance and articulation across the useable frequencies. I find that this provides me with more options not just for yielding a variety of tones (and I play a wide variety of music), but also for dealing with room/stage anomalies. That said, other folks like to have a "signature sound" that they can nail just by plugging and playing. While I find that I can get "my sound" quite easily with EA or Accugroove cabs, many folks love the Aquilars in this regard. To strike a middle balance in this equation, I find Epifani cabs to definitely have their own sound, or coloration (at least compared to EA or Accugroove), but to also have more midrange articulation and better balance than the GS112. Still, the Epi T-112 by itself lacks a bit in the upper-mid department for my likes, which is why I like to pair one or two T-112's with a T-110UL. This is really a wonderful combination.
Another great combination is the Bergantino HT112/EX112 stack (or just two HT112's). The Bergies have some of the best midrange out there, and the smooth and detailed high end that you expect out of Bergies (or Epi's). I do find one HT112 to be somewhat lacking in the low end department, though. Compared to a T-112, it's not even close. However, an HT/EX stack is fairly comparable to the T-112/T-110UL combo.
Yet another 1x12 that I have to mention is the EA Wizzy. This little marvel has no tweeter, but with its wizzer cone, you will have more high end than you think (just not the sparkly high stuff). It is another cab that excels at midrange, although with a warmer tone to it than the HT112 (which I would describe as more "hi-fi" in comparison). The Wizzy somehow combines the "old school" warmth and roundness with excellent clarity and articulation. It is a very lightweight cab that really puts out a lot of volume for its size/weight. Of course, the unpowered Wizzy is a 4 ohm only cab, so this will be a factor.
Finally, you may want to consider some of the 1x12's from the smaller manufacturer's out there. A lot of folks like the Avatar cabs (which I have not heard). Dr. Bass makes some exceptional cabs (I own some prototype 2x10 and 1x15 cabs from him), and others have posted about his 1x12's. Don up at Low Down Sound in Detroit is a true craftsman as well, and I have heard many of his cabs, including several different takes on the 1x12 design. I tried a high-power "GS112-like" model, as well as one with a coaxial design (which I loved, but which didn't handle a ton of power - at least that particular model didn't). Any of these manufacturer's (as well as Joey Nahas, if he is still making cabs) are also well worth considering.
I did try the Eden 112XLT, but to be honest, it did not impress me. To be fair, I had just been listening to Epi and Bergie 1x12's, as well as the various long-throw 8" cabs up at LDS, so it was up against some stiff competition. FWIW, I do own (and probably will be selling) an Eden 212XLT, which I happen to think is one of their best sounding cabs (along with the T-210XST, but that is a different story...).
Hope this helps, Tom.
With that said, I bet the sm500 would sound good with the aguilar 112 cabs.
