It's a badge-engineering job - fairly sure it's made by the very capable Chinese company Medeli - you'll find identical models badged for Alesis, G4M, Johnny Brook etc. etc. Like you, I've owned a used one which came and went for beer money. Oddly enough I found it more playable than the Yamaha equivalents. Good fun to have and useful for reminding yourself how to play the riffs you've forgotten! Not really suitable for anything other than home use (the sounds are unsurprisingly old-school - low-res and not very expressive) although some players use them as an add-on to a larger e-kit to add percussion effects rather than allocating full-sized pads to cowbells etc. Enjoy it!