This amp is perfect for studio work, and the occasional "quiet" jam. (See below for how I use it with a drummer). My Champ stays clean until about 5, gets warm around 9, then is wonderfully overdriven at 10. My amp tech, Butch Colclough (BC Electronics, Durham, NC) has modded mine to tweed specs. But the best thing he has done for this amp is the addition of a power attenuator (or load dump switch). One flick of a switch and the 6 watt beauty drops down to 1 gorgeous watt. Perfect for demos late at night in my little home studio. All the tone you need at listenable level. This amp sounds best with single coils (G&L Asat Classic is my axe of choice). My stock speaker was wasted so I replaced it with a Weber and it sounds great. The perfect studio amp, and with only three tubes (and class a) minor maintenance is easy. Nothing to re-bias.
I have been using this amp in conjunction with a Princeton (or a Princeton Reverb, both Silverface) and that combination of tones (by way of a Lehle a/b box) is the best that Fender has to offer. The overdriven tones come from the Champ, the clean tones from the Princeton/Princeton Reverb, and the volume of the two is loud enough to play with a drummer! It doesn't get any better.
My basic application is as a studio amp, so a backup is not an issue. Since I bought this amp (about a year) is has been wonderful.
This is one of the wonders of the amp world. A truly fantastic, tone machine. I've been playing over 25 years and have played HIWATT, Roland, Laney, Fender (various), but the Champs and Princetons cannot be beat. If it were to go missing I would replace it immediately. Thanks to ebay they are still fairly readily available!