First, from what I understand the power rating on these amps is pretty conservative. They actually produce more clean power than advertised.
IME, you can get a lot of mileage out of these amps with an efficient cabinet. I've used mine on gigs with a 4-ohm Berg AE410 and was surprised at how loud it can be. I'm currently in a country band that is pretty low with its stage volume. I'd feel comfortable using this on most of our gigs where I had PA support. However, I bought it when I was in a relatively loud modern rock band. I used it on a few gigs with that band where I had to keep my stage volume down, but for the most part, I would have gotten buried on most of our gigs. And my guitarist had excellent tone - never a mid-scooper, so it wasn't like I was trying to be heard under some ultra-bassy guitar sound.
Bottom-line, personally, I think it's a great amp, but I wouldn't buy one with the intention of keeping it as my main head. It's a great amp for gigs where you don't need a lot of stage volume and you want something easy to shelp. Seriously, this is the easiest head I've ever had to carry. My case full of cables and misc. gig items is harder to carry than this amp.
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