The DM5 rack and mounting hardware is superior (larger and curved main tube, extra supports, main tube height is adjustable).
The DM5 module is an actual Alesis engineered module. It's very reliable. Voices and controls are well done, but it lacks a lot of the 'stand-alone'/all-in-one features of other drum modules (inputs, built in metronome, sequencer, etc). It is just a midi sound source with a trigger-to-midi interface stuck to it. No bells* and whistles.
The DM6 module is a re-brand. Everything on the DM6 is re-branded. The DM-6 module lacks trigger control features (cross-talk, senstivity, gain, velocity curve, decay etc) and a lot of sound module features (proper outputs, aux outputs, midi in).
DM5's electronic drum voices are very high quality, but the acoustic voices aren't great and there is a very limited selection of acoustic sounding sounds.
I've seen new DM5 pro kits on clearance for less than DM6 kits.
I'm pretty much a beginner too (at drum smashing anyhow):
- Positive: I like the DM5 module voices (but I'm more into electronic music, especially from the era that the DM5 was made in).
- Postive: I bought the version with Surge cymbals and I'm very satisfied with the look, feel and triggering. I will be adding a couple more Surge/Smarttrigger cymbals.
- Neutral: The 8" Real-head pads are fine for now. I know I will be replacing them, but they are good enough so that I'm not in a rush. 8" pads are too small, but I guess they will help with stick control.
- Negative: I also had to buy a bass pedal, throne, metronome and small mixer. That was $600 more on to the price. Not a big deal, and if you don't insist upon getting the best available, these needed add-ons would cost alot less.
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Actually it has 3 ride bell voices, but that's not the type of bell I was referring too