I support the other reviews on all their positive points. There are two things I'd love to see in firmware. First, while it can follow an external MIDI clock, control over the various functions is very iffy and not ready for prime time. As the overwhelming majority of users won't go any further than a MIDI clock (if that), such overall control is a non-issue. The second thing is also a power-user thing and of little concern to the majority of users – something that has TC's TonePrint users spoiled rotten – the ability to get into the guts and tweak the daylights out of everything. As this is not a mod pedal, which might have a ton of FX buried deep inside (as with many of the TonePrint-enabled devices), the inability to engage in such brain surgery is also understandable.
When it comes to timing your loops, this comes with practice. For myself, coming from the world of multitrack tape (with all sorts of punching in and out, compensating for manual flanging - with the thrill of hitting the cross right on the beat, etc.) I honed the ability to punch in at 1/64th before the beat. For those who are new to loopers, the trick is to start and end the loop on the same exact sound and not at the very instant the pick hits the string. No matter. Practice makes perfect. As the device's second looper can be synced to the first looper, you have to learn to anticipate the beat as a matter of course, as the number of loop 1 repeats between loop 2 taps is determined by tapping the loop 2 switch before the end of a loop (which automatically stops loop 2 recording at the end of the current loop 1 cycle.). If you try to punch out right on the beat instead of offsetting your timing, there's a chance you might miss time it and end up with an extra loop 1 cycle (such as 12 loop 2 beats instead of the 8 beats you were wanting),
Note that recorded audio can be saved via USB as separate right and left channel audio files and transferredback to the unit. It is also possible to take any audio you have – music, a drum track, barking seals, Al Pacino being pulled back in, or whatever – and transfer it to the Ditto as a loop. This is great for when you come up with a loop in practice that you later want to use in your live show.
About the physical characteristics of the device itself, it is sturdy but not overly heavy. While it has a pair of wide optional stick-on rubber strips you can apply to the the bottom, that won't help much with a lot of surfaces, so it is worth it to velcro it to a pedal board. It has an ample selection of ins and outs on the back (including stereo) but other than MIDI, power and USB, they are all Hi-Z quarter inch.