The things said above are spot on, but let me add a little.
C-30's are, indeed, good all-rounders, good for blues, country and rock, jazz probably, but not quite nasty enough for metal and such- but using a pedal you can get there or at least very close. 2 input channels, switchable at control panel or via foot switch. No master volume, but the drive channel has pre- and post- gain controls, so you can get decent dirt at bedroom volumes- but you are not driving the power tubes that hard, so it won't be great. Pretty good reverb, although the only reason I can figure for it being foot-switchable is because Peavey likes 2-button foot switches and there was nothing else to control.
It's a good-looking amp, with tweed (or available black tweed) imitation tolex and chrome-plated control panel. It's narrow-panel front does a good impression of a Fender's look. 30 watts is good power for many beyond the bedroom situations, but you can get drowned out by a loud drummer. Just ask him to learn how to
really play. Then duck- he'll be a one-stick player for a few minutes after that. Seriously, 30 "tube" watts are about twice as loud as 30 "SS" watts, so you are about as good on volume as, say,
a Peavey Bandit (another very good amp.)
Best to buy used, IMO, not just because of the savings (you can find them, used but nice, for about $300 or so,) but because they are now made in China- Peavey used to take real pride in being "Made in the USA," but market forces changed that.
I had a C-30- it was my first all-
tube amp except for the Monkey-Wards Model 6000 "radio tube" amp I had as a teen. I was very happy with it, but I wanted on-board tremolo (the MW amp had tremolo, and I have been fruit for that stuff ever since,) so I bought a Delta Blues 210. Same amp but with tremolo and 2 10's (also available with 1 15.) I liked the look of the C-30 better, FWIW, the "TV front" look never did it for me. Only sold the C30 because I didn't feel the need for a backup, and then only sold the DB210 when I scored a SF Deluxe Reverb way cheap, and the Fender was everything the Peavey was, and more. But not
a lot more. Reverb was deeper, clean was Fender's famous bell-like chime, and everybody ohh's and ahh'd when I walked in the room with the DR. Remove the Peavey logo from the attractive oxblood grill cloth and most folks won't even notice you aren't playing a Fender- the newer ones with the logo in an oval don't pull that off as well, which is another reason to buy used.
If I felt the need to trim the cost of my rig, I would probably sell my DR* and buy a C-30 or DB-210- and the extra $1200 or so would be nice, too. You are probably at about 80-90% of what
a Deluxe Reverb is, with a C-30/Delta Blues, at about 20% of the cost. Both your guitar guru and your financial advisor would approve.
*Actually, the DR lives and works at Studio101NOLA, and I play through a Ampeg Jet J12T, these days.