I owned the Decatone for a few years. Never owned an SLO, but have played a few. The clean is very clean not compressed. Hard to get it to sound thick, but takes to pedals well. It's very nice, but I am more into a Fender clean, say a Vibrolux or Bassman. This is different, but still good.
The Crunch channel is where I spent most of the time. Also not as compressed as you get with an SLO. It's in the hod rodded Marshall territory. Very good.
The Overdrive channel is supposed to sound more like the SLO. It is voiced like it, but not as good IMO. If you hadn't played an SLO you may love it.
Overall, it is a Soldano and is built well. Check out some of the reviews on Harmony Central. Some people swear by it. I sold it, and haven't missed it that much. But don't take that to mean it is a crappy amp. We have all sold very good amps in our day.