I've got:
- Roland TR-727
- Roland TR-808
- Roland TR-909
- Roland CR-78 (speaking of which, I just came across a
wicked article about how to program a CR-78 with a Kenton box and a Korg Electribe. I haven't got the latter, but with a little tweaking I'm sure I can get it to work with my Kenton and the 727 or 909. Now all I need is to wire up some individual audio outputs)
I've had a Roland TR-707, but I sold it as I really didn't feel that I would use it considering what I've got. I'm somewhat interested in getting a Roland TR-606, but I'm far more interested in getting an Oberheim DMX and a Linn LinnDrum (someday).
Personally I love the timing of these older drum machines. I frequently compose a few patterns on the machines themselves, record them to my computer, and then build the rest of the track's instrumentation around that. If I've composed something on the PC, I'll often use a software drum machine or drum samples only as place holders, and break out one of the drum machines to take their place later on (with the exception of anything glitchy or drill/drum & bass mind you).
I'd recommend everything I've got, as their fantastic to use -- though the TR-727 is
somewhat a nice machine, so it may not suit your styles.