I have played this kit on a daily basis for around nine months. I have never used the stock heads, only Evans Calftones so this review is based on that. I also picked up the extension 10" and 14" toms after playing the kit for a while.
On the bass drum I use Calftone EMAD on the batter side and Calftone EQ4 on the front, no additional muffling.
I love the sound of these drums! They are lightweight and the hardware is simple but functional. The tone is dark and a little wild in terms of overtones. With the EMAD heads the bass drum gives a nice tone without too much sustain. The snare sounds best tuned medium-low for it's size, but also works fine in a higher tuning.
I it works well for low volume playing as it is on the quiter side for a drum kit, as well as it's small sizes and the way it sounds with more open, natural, ringy tunings.
The smaller of the optional toms have surprising sustain given the simple mount. The floor tom is very shallow but sounds convincing. Both toms sound best to me with a low tuning.
With the lightweight construction they can feel a little flimsy and are not well suited to heavy hitting (not their strength soundwise and may not hold up to abuse). I would not recommend this if projection/ high acoustic volume is needed, nor for playing heavier music. But for acoustic, natural, jazzy tones it's great.
It's extremely portable with the shallow bass drum and floor tom and small sizes. the dimensions of the bass drum also means the footprint is small on stage. The mount for a percussion arm or stand on the snare drum is a nice addition, perfect for a cowbell arm. The mount for a cymbal arm on the bass drum saves having another stand. I wish the cymbal arm was included though as it would be a waste not to use it if portability is a concern.