Digitech Whammy DT

I had my reservations, wondering if I really need this pedal. It felt like a novelty/gimmick product. But now that I have it, I actually use it very often! The drop tuning function is particularly useful, because I can quickly switch to -2 semitones or whatever, and it sounds just fine!

Caveat: Notice that there is slight delay/lag (a few milliseconds) when using this pedal, so it wouldn't be comfortable to play fast shred solos with the drop tuning function ("The Drop" pedal has the same issue). However, for normal riffing and slower parts, it works just fine. Now I can simulate playing heavy 7-string riffs :)

Another caveat: Notice the power requirements, as this pedal is much more power hungry than your average pedal. I use it with the 1Spot CS7 power supply, 500 mA output. It works just fine with that.

For years now I've been wanting to try out this one of these pedals. Some of the world's most renowned players (Tom Morello, Johnny Greenwood, Joe Satriani) have made them a mainstay of their pedalboards so much so that their sound has become synonymous with its pitch-shifting capabilities and unique traits. Apparently to some 'aficionados', the original WH-1 from the early nineties is still the gold standard with recent subsequent models (WH-4 and 5) fairing less favorably with fans. However, with the DT and its new features (droptuning and momentary switch) I think Digitech are finally quelling complaints from long-time fans of the original.

Pros
Really easy to set up and use.
New features like the droptune function means no more retuning to play certain songs (eg. you can play in Eb or F at the touch of a button).
A lot smaller than i thought it would be so more compact.

Cons
Included power supply is odd looking and means if i break it, I will need another specific digitech whammy power supply as apposed to just a generic 9v one.
Droptune function isn't perfect as there is a noticeable delay from the time you pluck a string to the time the sound comes from the amp.

The whammy DT can make a lot of interesting sounds. I've had it less than a week and have learned a handful of songs that I can only play using features found in the unit. You can mimic an octave pedal, a 12 string, I've used it with an 8 string guitar and a 5 string bass, and you get all sorts of interesting results. I specifically got it for the ability to drop tune without changing your instrument, and the whammy part is just a bonus. If you're down tuning more than 3 half steps down, the sound degrades, but I'm fine with that. The sound quality is quite good and it fills in the spots on my board I needed it to.

I'm gonna start with the downsides. This effect pedal introduces a slight amount of noise and a hint of digital 'garbliness' to the tone, especially when hitting a high-gain amp which exaggerates these tonal side effects further. If you use this as a part of a long pedal chain, you'll want to experiment with placement to find where it suits your final outcome the most.

Having said that, this box is much about sound mangling anyway, and the negative aspects are minor compared to the tons of fun you'll have when dive bombing and messing up your solos. Adding harmonies works as advertised, faux 're-tuning' sounds surprisingly well (e.g. for dropping those metal djent riffs on your standard tuned Gibson with cool results), and the whammy effect can be extremely fun when not overused. As with all digital pitch tools, the sound quality for static sounds works better when you don't go overboard range-wise, keeping the aforementioned garbliness to usable discretion.

Think Tom Morello of Rage Against The Machine, and the picture should start making sense.

An overall great and versatile pedal that is way more than a one trick pony.
Does all the classic Whammy sounds well(covers all the Muse ground, Gilmour too), but it can also be used as a killer chorus pedal with the detune settings, or a "Any Colour You Like" sort of sound, and the MIDI port allows all sorts of sequencing. And of course, the drop tune side works great as a capo or down-tuning, and it pulls a convincing bass sound if you're not picky.
However, the further down/up you go, the worse it performs with more than one note ringing and it could be a problem at the extremes. It's also quite noticeably "digital" (trebly, harsh) when shifting up. It could be seen as the characteristic sound of the pedal, and it sometimes works, but it's not perfect. Otherwise, it has great tracking, slight lag when the pitch is shifted, but that's inevitable and not distracting. True bypass indeed, no tone sucking, and it's built like a tank.
There's still room for improvement, but it's great at what it does and it's not only for Muse and Morello, it's a jack of all trades.