I've replaced the original speakers which didn't sound all that great, with Ceramic Sig 8's from webervst.com (an awesome company if you don't know them check them out) - man now these little amps sound incredible, clean, or distorted, or many places inbetween. VERY versatile!! Roll all knobs to the right, and you're in for a treat.
The way I'm playing the is in stereo coming out of a rocktron intellifex, with Ebtech hum eliminator on the lines out. 1999 Am Std Telecaster or 1956 Gibson ES125 - in any case all single coils. Very light effects, just a touch of reverb. There is so much you can do straight with these amps, and just your volume, and tone on the guitar. 6 Watts, but man, now with the two amps together, I cannot crank them up too far because accidentally going to the bridge pickup on the Tele and it would slice my torso in half. Yes, they are loud.
In a world of electronic crap these little tube amps are the real deal. The overdrive like distortion is so nice when cranked.
These seem super reliable. Though if I was a professional musician I would definitely have a full set of spare tubes on hand.
If I lost these amps I would replace them immediately. As a matter of fact I'm thinking of getting two more now, just to have on hand. I bought these sight unseen (unheard) off eBay because I heard all the raves, and was not disappointed. I must also emphasize what an improvement the Weber speaker was, and the Weber people were super helpful when I ordered.