Just remember that if you're planning to do any serious recording, quantity of sound outputs is important.

I don't know how many outputs the TD-8 has (haven't got the specs, which is why I posted the earlier question) but make sure it's at least 6. Trust me, if you're planning to do serious recording with the unit at any time in the future, an extra 2 outputs is worth double the money.

I run an R-8m (because I'm not a drummer) and it usually breaks down like this:

Stereo Out: Overheads (cymbals in stereo).
Mono: Kick.
Mono: Snare.
Mono: Hats.
Mono: Tom.
Mono: Tom.
Mono: Tom.

That's 8 outputs. Don't be thinking you're gonna get away with less if serious recording is involved - especially if you're recording "live" playing (sequenced you can just do two passes onto "tape" and change output assignments in between).

If you're only gonna do hobbyist stuff, then don't worry about quantity of outputs (mind, do plan for whatever the future holds - Roland gear will last you a lifetime if you treat it properly).