shoegaze

Well, it did sound good loud!
I haven't gigged in years, but my mate Jon from the Posies has used it, and he really liked it. Then again, he's a big fan of 70s Twins. He got a great sound from it at a reasonable level.
My one's a '75, with the master volume control. It would seem that there's a lot of people out there who don't like 'em.
If I do ever decide to play live again, I'll get another and run them in stereo.

Do you guys have any suggestions for decent amp heads at about the 500$ range?

If you only have $500 in your budget I'd e-bay a used one. It's hard to get a decent new amp head in that price range.

I don't know what kind of sound you are looking for or what kind of cab your trying to drive but I can tell you a few heads I think are worth looking into just based on the sounds I like:

Ampeg, Lee Jackson series... you can get the 50 watter for around your price range and it sounds a lot like a Marshall plus it has a plexi-glass logo with a purple light behind it that looks wicked cool on stage.

Sovetek, Mig 50 or 100, again sounds a bit like a Marshall, these used to be dirt cheap but I've noticed prices going up recently. Looks kind of cheap but sounds good to my ears.

Roland JC-120h, sounds just like the other JCs but it's a head, a nice clean solid state amp that cranks out some serious volume in true stereo and loves pedals. You should be able to get one of these for around your price but they don't show up on e-bay very often so you may have to be patient.

Okay, that's it for now, I'll post some more if anything comes to mind.