I bought the SR-18 to replace my old Zoom RT-123 that finally started failing after over a decade of serving me well.  I have a full computer recording setup with high quality drum plugins but I still love the vibe and hands-on immediacy of a good old-fashioned groove box, and the SR-18 does not disappoint.  It sounds better than I expected, with a good selection of surprisingly decent acoustic kits, but it's those deliciously dated kits and samples I actually like the most.  My philosophy is, if you're going to use a standalone drum machine these days, embrace its mechanical nature and look to software if realism is what you're after.