Thanks for all your suggestions, dudes. Here are my thoughts on them...
HR-50 (and 50+) is, indeed, quite a bad ass amp and it does get pretty close to the SLO, but when you actually compare them the SLO still blows the HR50 out of the water. Its like Fajitas and a Porterhouse. Fajitas are great, but if you've got both in front of you and take a bite of each, you're going for the Porterhouse
The Jet City sounds absolutely nothing by Soldano and, to me, sounds like junk.
The Peavey 5150 (now 6505) is to an SLO100 what an Epiphone Les Paul is to a Gibson Les Paul Deluxe. I also found the Peavey to be a bit too sizzly with a lot of shrill. It seems that they tried to capture the sizzle of the SLO's overdrive, but didn't quite get it right and actually went overboard with it.
I looked up the SLO Clones and found the Weber Heather to be a pretty decent option. The guts look good, but the chassis looks like crap. C3 Amps looks great, but I'm not sure the guts are as good as the Weber. The Weber will have you around $1150 out of pocket shipped. The SLO can't be had for less than $2800. So this is a viable option that I am seriously considering.
The SLO setting called "US Hi-Gain" on the Toneworks Pandora sounds pretty sweet and its what I use for now when I'm jamming late at night