Always wanted to try the Chase Bliss Warped Vinyl. Looks like there's not much it couldn't do. I've got Moog Clusterflux... great sounding chorus, almost surgically clean (which isn't always a good thing). It probably comes closer to the Boss CE-1 sound than anything else I've tried (including old CE-1s that are usually noisy and the Retro Sonic Chorus).
Also wanted to mention the Ibanez SC10, sounds very close to a Boss CE-2 and can still be found cheap. The old MXR Stereo Chorus and Micro Chorus are really nice, too. Both used the SAD1024 or SAD512 chip (in at least one revision of the Stereo Chorus). There's an old DoD chorus that does, too. I don't have an old Ross chorus, but I do have an old Ross Flanger, and that thing is just amazing (SAD1024). Analog Man's take on the Small Clone is pretty nice, too.
I'll admit to being a little bit of a chorus junky (more accurately, modulation junky, since I like flangers, phasers, etc., too), but I am extremely picky. I've never liked the seasick sound that was way overused in the 80s. I much prefer slow, subtle movement, basically like EVH used with the Phase90 on the early VH albums.
I've run chorus both before the amp and in the loop. Both sound good, but different. For me, it just depends on what I'm going for.