Many of these low-wattage lunchbox amps start distorting VERY early in the volume taper. I don't like that. If I want distortion, I'll kick an OD pedal on or select the OD channel of the amp. I want my cleans to stay clean at most volumes. And I mentioned girth and punch too. A higher-wattage amp can sound massive, even without going to ear-splitting volumes. I've owned most of the lunchboxes and they all sound smaller/thinner than the big iron, yet get nearly as loud. Considering the fact that many higher wattage boutique amps have great volume tapers, it seems like a win-win to me. People who buy 15-20 tube amps thinking they're going to get cranked feel and tones and conversation volumes are fooling themselves. I learned that early with the first release of the Marshall Class 5. The only way to do that is an ISO cab, or maybe an attenuator. But then that cranked tone gets a choked, or blanket-over-speaker quality.
I do remember the Engl Ironball sounding pretty thumpy for a low-watter though. That little pig is heavy too!