can anyone help recommend electronic drums for a gift?

Hello,

for christmas this year i would like to get my friend a set of of electronic drums that he can use to practice at his apartment.

I know he has a pretty decent acoustic set that he uses with the band, but I think it would be cool if he had something to use to practice on.

I was wondernig if I could get something decent for around $500 us and if anyone could recommend something. I would like to order it online if possible.

Recommendations would be great so I dont have to order blind on musiciansfriend.

Thanks!