Found an old thread where I shared some of my thoughts:
http://www.drummerworld.com/forums/showthread.php?t=93310
In short, if most of your set is
below about 200bpm - you will benefit from it. It's not so useful for faster music, especially double time punk/metal type grooves, and the reason is tricky to explain, but it's not the device's fault (it's the drummers
). The reason is that at higher tempos your snare needs to be unrealistically accurate for the Beat Bug to give you a steady reading. The Beat Bug doesn't have any kind of averaging or tolerance feature, it just gives you raw measurement between two consecutive notes.
Here's a review of the Tempo Ref
http://www.youtube.com/watch?v=4YFybJwEVKg
When he plays the 200bpm groove starting at 6:00, it gives a fairly steady reading, but when he goes into double time you see the numbers bouncing all over the show.
The included trigger works fine, but it doesn't come with a proper way to attach it to the snare. I've been told that any acoustic trigger would work with the unit, so if you wanted to 'upgrade' you could just pick up a trigger from Roland, ddrum, or the like. The unit also doesn't have it's own mount - I'm keeping an eye out for a clip on mobile phone or iPod holder that can hold it.
I believe this thing is homemade, by the inventor himself, probably in his house. While that may sound like an overflowing bucket of reliability hell, I have had mine over a year and it still works fine and the benefits of having it have more than outweighed the cost. If it broke I would buy another one straight away.
And I chose the Beat Bug over the Tempo Ref because I did not need the extra functions of the Ref. The Ref's auto power on/off sounded a little fishy too, based on what the reviewer in the video above says about it.
Any more questions just ask