I use a Zoom ST-224 Sampletrak, myself. Nice device, can run a number of loops without synchronization of different lengths, ergo I use it for backdrops. The constantly varying VLF and shortwave noises throughout this work are all running on the Zoom: https://daccrowell.bandcamp.com/track/umi-no-kami-ni-kansha
Other than that, which is pretty different from looping as shown here, I do all of the rhythmic loopwork in Ableton Live. And theoretically, there's several other devices in here that can also serve as looping devices, and technically I can get signals from the modular "sandbox" to the other side of the room for control (if I don't use MIDI SYSEX for it, that is).
I'm also in the "study phase" of a work that's more for installation purposes which will use my Akai S6000 to play numerous LONG loops, ala "Music for Airports," but more complex in timbral diversity. I don't think I can get that working until I refit the sampler with a Gotoh or Nalbantov FD-to-digital media device, as the longest loops here will be up to around 10 minutes, and these add-on devices enable storage in the hundreds of gigabytes.