I have a madbull chrony (black...I think it's the second version) works like a charm. Alu. Construction runs on 2 AAA. There are 5 modes(I think. Sorry I don't have the unit in front of me just going by memory) fps/mps/rps/rpm/joules by weight selection. It is rated to be one I the best in terms or accuracy. Very portable. it's a little larger than your fist.
The modes are displayed by cycling through the unit. There are other units that displays all the info at the same time, but the problem is the numbers are rather small. My unit is um.. Big