I use TD3 + Alesis Trigger IO and it work great with S2, i made my drum with piezzo on acoustic Pearl Traveler Gig Drum and Mesh heads.Trigger is for Toms/Rims, Ride Triple zone, Snare Piezzo 3 and some addons like cowbell etc… TD3 is for Snare/rim, bassdrum , cymbals, and Hihat, i use a midi usb for the TD3 and put in Trigger IO in TD3 or even i can use Trigger IO usb too . Very happy with this config but a bit long to setup, i’ve tested TD20 in some music shops and friends and i found it suxxx like hell