I've had a bunch because I play tabletop noise and I fit as much stuff as I can, into a limited space (suitcase which I can carry on the subway). Small means more toan options for me. A mini delay opens up room for other things.
Mooer Trelicopter - I wanted hard chopping, but I discovered it was pretty subtle. My fault for buying the wrong thing.
Mooer Pitch Box - like Boss pitch shifter (?) I use the Harmony setting for thickening & dissonance. Don't know or care about tracking. Like!
Mooer Reecho - I like this a whole lot, but then I like simple delays that are not hard to dial in.
Mooer Repeater - like this but I like the Reecho more. Has longer delay than I need, so dialing it in is more careful.
Mooer Shimverb - hated this, YMMV. Sounded metallic in a bad way. Didn't want the shimmer either.
Mooer Mod Factory - good way to get a bunch of modulation options into a small box. I only use a couple settings. No idea if tone sucking or not.
Mooer The Fog - supposed to be a Wooly Mammoth clone? Adds nice grit in my SuperEgo effects loop (not tabletop)
I'm really interested in the Mooer micro pre-amps, but I think they work best on amps with an effects loop (which I don't have). Make your amp sound like a Vox, Marshall, Mesa Boogie, etc etc.
Mooer released a bunch of new pedals (reverbs etc) which look interesting.
When they launched the line originally, they were priced around $40. I use that as a benchmark and I try not to pay more than $50 for anything
Mooer, Eno and Mosky rat clones - I like and use them. I don't have golden ears, and I'm not a rat expert though. I never A/B'd them against each other.
Meathead clone - nice as a dirty boost, etc. Accurate clone? I don't know. Found on Reverb. Like it!
MXR Phase 95 - has multiple phase options (script, block etc) in small format. Like it!
TC Electronics Sub & Up - do not like TC Electronics in general, or this pedal specifically.
TC Hall of Fame Mini- the whole Tone Works concept is flawed IMO (please, don't make me program it). Sold it.
TC Flashback Mini - kept it, but questioning my decision.
TC Electronics Vortex - (vibrato) I found a setting that has 3 different modes/speeds, so I kept it.
Overall, I think TC pedals sound kind of artificial and I hate the Tone Works thing (dozens of presets available, good luck sorting through them). Maybe my least fave company.
Catalinbread Ottava Magus Mini (octave up fuzz) I did not like this. Sounded worse than other octave-up pedals I've tried. (not tabletop)
BYOC has some micro kits now (muffs etc).
Ditto Looper - I like them.
Eno Looper - I just ordered it. The biggest knob slows or increases speed of the loop (or pitch). Looking forward!
Donner Echo Square - it can reduce or increase speed of the repeats (with fun artifacts) but I think it sounds terrible overall. Avoid IMO.
Eno AE-1 Ambient Echo - I thought it sounded terrible, metallic but not in a good or interesting way. The call it "ambient" but the delay time is short. Worthless IMO.
Micro Thumpinator - rolls off frequencies below 30hz for bass players (supposed to clean up your sound) but I find it rolls off some useful frequencies. I like my bass tone better without it.
Hotone tuner - seems to work okay! Has a boost option.
I would like to try the Zvex Fuzzolo but I don't want to pay 80-90 dollars.
If I had a choice between soft touch footswitches in a regular size pedal, or clicking footswitches in a micro pedal, I would rather have the soft switching in a larger enclosure.
F-Pedals makes a micro ringmod: the Robotholic.
MythFX Infinium Delay has a ring mod function.
There are some mini-pedal comparison videos listed here:
http://www.effectsdatabase.com/type/ringmod/pedal/mini
Micro versions of classsic pedals seem like an additional revenue stream for the big manufacturers - EHX should do that with their Muff reissues.