So it looks like it may map to the general GM notes:

Instrument MIDI Note Assignment
Kick C2
Snare 8 D2
Snare 9 E2
Low Tom F2
Mid Tom G2
High Tom A2
Closed Hi Hat F#2
Open Hi Hat A#2
Cymbal C#3
Rimshot C#2
Clap D#2
Cowbell D#3

As long as those are the only hits I need, that is fine. It also says you can also use MIDI note messages to select Tattoo's active pattern. -and- It transmits velocity values as set in each instrument's velocity sequencer.

I am wondering is someone with this and Reaper can try to create a couple bars with pattern changes driving an external plugin, then use Reaper's 'Apply track FX as new take (midi output) feature. So essentially in this scenario I would use Tattoo to program patterns, then render them to the piano roll and disable Tattoo. But now this is sounding more and more convoluted.

OK, so I'm back round to the iDrum again, I installed it on my main machine and it is running just fine, I'm going to look for the cheapest possible copy I can find, and get a decent skin for it eventually. It just is the simplest solution, outputs midi files nicely to GM format (at least using the 'Acoustic light rock' kit, and doesn't sound as bad as I thought it did through headphones on my laptop last night. Just the ease of writing velocity changes is too much for me to pass by, nothing is quite as easy. If anyone wants to submit an offer, I'll consider it, so PM me. I can get a copy for $28 shipped, so if you can beat that... I will go look for some money in the change jar.

Edit: no money in the change jar, maybe next week. But still taking offers I'll post something in the market when I have cash on hand to pay.

Nerve is like iDrum.

http://xferrecords.com/products/nerve

Yes and it's also $200!

Devs must eat too.

Certainly not disputing that, just way outside my measly budget. Even $20 right now is a stretch so I'll probably get it sometime in the next few weeks, but just throwing it out there

a. I think I made up my mind that I can't find a suitable alternative for the price and

b. I'm kinda in the market for it. Everything else is overkill, and I do want to mostly work in the piano roll, and iDrum is a nice little tool to get the notes I want into the roll. But not worth $55 to me right now, since I could do it directly and maybe even get better results than everything I've seen so far. Everything has its limitations, price or stability, or no demo version, or midi to piano roll, iDrum seems to be actually what I'm after, just I have no cash.

And the dev/producer, Steve Duda, is a cool cat (or should I say cool dude-a? ). I have the Nerve demo, need to try it, but same deal---price is high. He has some nice free plug-ins on that site too, BTW.

hi braj,
I am the developer of Groove Drums (IMEA Studio), I thought I made a simple interface, apparently not.
I'm surprised you find the sync is not right, it is used on various DAW (Cubase, Ableton ...) and I never heard about that !
I'd like to know more, it would help me to progress.

I'll have to reinstall and take another look at it and get back to you, I didn't spend much time with it.

OK, I didn't see the timing issues that were there on my laptop, essentially as I recall it wasn't starting at the beginning of the measure properly. But maybe that has something to do with the CPU usage on the laptop, I don't know. I do have to say the UI is pretty dark, hard to read, the sounds are not really what I'm after, I couldn't get the drag and drop of midi to work (demo limitation?). I'll keep playing with it though, but it isn't really what I am after sound-wise. iDrum is still at the top of my list based on price, I found it consistently for under $30. I keep putting off ordering it though, it sounds ok but a bit thin, it will take some external processing which I guess is to be expected. But the big + is the smooth pattern writing, that's really appealing to me. I don't use electronic drum sounds so much so this has been on the back burner waiting for funds.

I'm warming up to Groove Drums, I like how easy it is to add your own effects, that works well for me. I do wish you could just drag and draw the drums hits though, is there any chance to get this working like in iDrum, maybe with a modifyer key? Also is there a possibility of reskinning it? I'd like a lighter version of the skin personally.

If I try and put MixControl Pro as an insert within GrooveDrums it crashes Reaper. I guess I shouldn't do that Anyhow it isn't badly priced, I'll have to compare it with the new DK+ 2, still iDrum beats them all with price and my needs are pretty meager. I do really like having the two sends within the plugin so I don't have to send to separate channels to isolate reverb and delay on the drum tracks.

Well GrooveDrums looks compelling but I think I am going to be super cheap, I put a WTB add up in the market for $30 for anyone that wants to sell their iDrum license. Eventually I may get a heavy-hitter like Geist so I want to spend the bare minimum right now and iDrum does what I need, if not much else. GrooveDrums definitely looks like a winner though, the EQ for each drum is nice, as are the effect sends, I'll keep my eyes on it and keep playing with the demo, and see how it develops.

don't think I saw this mentioned: Acoustica Beatcraft
http://www.acoustica.com/beatcraft/

practically looks like iDrum

Practically but oh so Win95 ugly though.