Well, if you've got an amp like that, then, gee, not sure why you'd care about the Spark. In my case, I like it. I've never had a non-tube amp before, but it fits my current lifestyle. It's very small and it makes a fairly pretty set of sounds at low volume. I've had it for a few weeks and I still haven't got it above a few decibels because I live in a studio in a Victorian with neighbors in rooms all around me and my getting shut down by the cops for jamming too loud days are long past. I really enjoy downloading amp/fx patches and trying all kind of different virtual rig setups, easy-peasy from my pad to the unit by bluetooth. Pretty fun. I like how well it works with headphones, and direct into the PC for USB recording; how I can monitor any kind of audio feed from the tablet into the amp, and then mixed with my guitar jamming into my headphones. All of that works really well for me. The tones are legit. An amazing thing for $259. Especially since I don't need any pedals since there's unlimited pedal fx with the software.
The axe is a low-end thing (a proper Gretsch would run $2000+) but totally gets the job done for $549. After a lifetime of Fenders and Gibsons I decided to mix the shit up. A lot of sounds I like, e.g. The Cult, AC/DC, are coming from a Gretsch. These are my first guitar and amp since I lost all my stuff in the fire in 2011.