I just had this Thermal exhaust system installed, which I got from the last group buy in late June/early July. Gotta say I'm impressed. The sound is great--low and growly, not high-pitched and "ricey." There's really no drone, either. You hear the exhaust when you get on the throttle, and it's reminiscent of my old 2010 Mustang GT growl (although it resonates through the ST hatchback differently than through a traditional coupe/convertible). At highway speeds, you can barely hear the exhaust, unless you accelerate. I heard more tire noise than exhaust note at 75mph.
The exhaust is also of high quality. The tip looks good, and isn't too showy. Fits the line of the car. The mechanic who installed it for me told me a couple of times that the system was really nice, and he said the muffler was one of the best he's seen. Actually, two guys who work at the muffler shop that did the install told me that.
This exhaust is noticeable, but I wouldn't say it's loud or obnoxious. You can wake the neighbors with it, but you won't automatically do so. It definitely responds to the throttle, though, which is nice. I would highly recommend it, if you're looking for a more baritone sound without drone. Even my wife said that she thought the car now sounded like it should have from the factory.
I also had a great experience ordering through PandaMotorWorks--they processed my order quickly and had it shipped quickly. I got the system on Friday, July 7, and had it installed on Saturday, July 8. Spent Sunday in the car driving around, and the exhaust performed great in town and on the freeway.
If I can get some video shot this week, I'll upload that and some picts. There are also two more good Youtube videos here (were in the last group buy thread, but haven't been posted here yet):
TL;DR--great baritone sound, no drone; highly recommended exhaust.