I own the Blackstar FLY3 Charge and actually bought this one as I had to top up an order to reach the free delivery limit. At first I didn't find a good sound out of the box, it's too bright, and kind of decided that it's what you get for the money.
After some tweaking with the settings I found some sweet spots where it shines.
As it's too bright, I keep the tone at 0 and also position it on the floor, placing it higher makes it unpleasantly bright even with the tone at 0.
With the dirty channel on, gain at 100% and volume at 50% you get a good overdrive (60s/70s classic rock, - God save the queen punk sound). Volume at 100% and gain at 50% cleans up to a good bright crunch, Little wing style. With volume and gain maxed it becomes a bit too loud for home playing. My Vox Amplug AC30 headphone amp has a similar range of sounds.
I don't think this amp is very versatile, the Blackstar will give you a much wider range of sounds/styles. But it's great for classic rock, rocknroll, punk, funk and there are some settings where it sounds awesome. The BT works great. For the price it's a great device and I'm definitely keeping it.