ReaSamplOmatic5000
Kenny has a 3-video series using this to create a live drum kit.
I'm starting to get into this ReaSamplOmatic5000 thing. I'd been wanting to go with SD3 or EZD3, but figured I'd try Reaper's ReaSamplOmatic5000 to create kits from free samples and see how it works out. They're more realistic than the MTPower Drumkit I'm currently using.
I started on this a couple years ago and got sidetracked with some music stuff. The drum samples I had downloaded somehow got themselves dee-leeted. So I started over with Kenny's 3-part video series on creating a live drum kit.
I have to say up front, the hardest part of all this is extracting the downloaded samples. Make sure you direct the extraction to the correct folder so they'll show up in Media Explorer when you go looking for them. That's it. Pretty easy from there on.
ReaSamplOmatic5000 lets you modify the samples in various ways to suit your ears, such as pitch; duration; etc. You can even pan each one L/R independant of the track setting. When using hi-hats you'll want to add the JS: MIDI Choke to the track's FX chain - included in Reaper's FX library.
I think the coolest thing so far is these samples can be added to a track via a MIDI keyboard and show up as audio waves in the track screen. Or they can be placed into the piano roll via step-edit and appear as MIDI notes in a MIDI item in the track screen.
Each sample can be assigned to any keyboard key or range of keys. If you load 5 samples of the same hi-hat with 5 different velocities, you can trigger the velocities from one key by the usual keyboard method, or assign each one to it's own key in a sequence so C2, D2, E2, etc. will increase in velocity - or add them in reverse.. whatever.
Maybe one limiting factor is getting enough samples. There are gazillions you can pay for - not so many freebies. But the freebies which are available appear to get the job done well enough.
I'm starting with the samples Kenny uses in his video :
http://juddmadden.com/drum-samples.html