I use this unit for 2 months and my favorite is the fact that we can change the settings of marks (accents volumes of black, crooked, doubles, triplets and overall volume) separately and easily. The backlight of the LCD screen and lights for accent and black are easily seen in the partial or total darkness. You can also quickly record tempos and name easily too. It is easy to change the tempo of each program. Possibility of chains (for someone who has several groups which often changes the order of his set). I tried the boss dr beat, but I did not like. Little sign of quality used among others by Manu Katche ...
The only downside so to say, be careful to replace the 9V battery pretty quickly because if it is exhausted or if it drags when changing presets are lost .... Solution: use up an adapter and / or check regularly the state of the battery
The quality / price / opportunity is unbeatable at the moment I would say.