Safe Bet Amp?
Is there such a thing?
As I begin to work on my skills at playing amplified, I'm thinking that it might be wise to get an amp and mic combo that I know works fairly well for harp... that way if it sounds like crap I know it is my fault and my technique needs work! I figure I'll get a bullitini, but I'm wondering if folks have suggestions for a safe bet amp that isn't too expensive. I'm not sure I'm ready to pay for a Memphis Mini, and I don't trust myself enough yet to evaluate old amps. Maybe the 5-watt Fender Champ (which is the vibro xd, correct?)?
You're right that a lower-wattage amp can get more distorted at lower volumes. The smaller amp you'll also commonly sacrifice bass. If you want to get distortion at lower levels, then use the distortion channel built into the amp. The Super Champ sounds better at lower volume than the Blues Jr. The Blues Jr sounds better at louder volume than the Super Champ. I feel the Super Champ is a better choice for you than the Blues Jr.
The Peavey Classic 20 and Princeton 112 are amps that can work for harp, but are not "known" for being really good for the harp. It sounds like you're serious about getting something good for the harp, so I now suggest you sell these two amps and get a real good amp. Spend the money, get something good, something you won't have to replace... like a Gibson GA20 (1950's), or Fender Princeton Reverb (1950's through mid 60's) or a Masco with a cool cabinet. That's my two cents.
I tried all of those and didn't care for them. If you can get your hands on a vintage Princeton, that's the way to go. You don't have to spend the $ on a blackface, the silverfaces through to late 1960's sound great.
I think the bullitini is a good choice. For an amp, the Fender Super Champ X2 is a good choice.