Ease of Use — 10
Incredibly easy to use but it takes a while to know which preamps/amp settings simply don't work on your guitar, for example I've found that the tube screamer distortion and similar effects just can't make a good sound from my strat, but like I mentioned earlier there are many ways around it. Like any amp could crank out metal and still have headroom for bluesy tone on another setting.
Editing patches is unbelievably easy once you get the general idea going. If you know what kind of distortion, reverb, and the tone you want on the top of your head, you could easily replicate it in minutes. If you're inexperienced with modelers it could take longer, but that's not because of the difficulty of the design in editing patches, but the inexperience of the user.
Sound — 9
The pedal out of the box, like most multi-effect-preset-driven effect pedals, sounds awful. After deleting a few patches and working from scratch, I can say the pedal fits any style. I used to run this through a PA but nowadays I run it through my headphones (ATH-M50X's) and it probably sounds far better in low-volume situations, as a generalization of those two experiments. The pedal is alright when it comes to noise, mostly where the noise comes from would be your guitar's pickups more than anything. The pedal itself doesn't make any noise. The "tone" knob is noise-attracting, though, and it is very noticeable if you play near any other electronics.
The pedal has a huge variety of sound from dark/muddy to obnoxiously bright, just to show that it doesn't lack any tone output. The tone knob has an amazing range of sound, and has lots of sweet spots. For example if you have a Strat you generally wanna make a patch with tone at about 9-13 o'clock, but if you want to switch to an LP you can adjust tone on the fly (no need to edit the patch) by using the knob itself, a neat feature that a fair bit of other effect processors lack *cough* Axe-FX *cough*
This pedal has neat generic rock/metal tones out of the box, but it can be tricky to get for example, a nice blues tone or jazz tone, because occasionally you might find that it may be better to crank the tone knob and drop the gain on a rock amplifier setting, than to actually look for the jazz amp settings (in other words, some settings aren't exactly the best, but it can be worked around and still sound marvelous).
Reliability & Durability — 10
This thing is would probably be military grade if it could be used in the military. There isn't anything that can really wreck this pedal. The little bit at the top of the expression pedal may come off but super glue it back on and no problem. No real damage to the unit. I've had this thing for almost 4-5 years and it's still shiny and good. The knobs work and they don't skip values. This thing is very gig-able particularly because of it's price range more than anything, very disposable compared to other processing units out there.
Overall Impression — 9
I'm generally very impressed with this unit, and it's amazingly cheap for what it delivers far more than at face value (it's shiny appearance). I've been playing since ~2007 and I've owned other pieces of gear (an Axe-FX Ultra) and I can say the ME-25 easily competes with the Axe-FX, mostly because of the Axe-FX's lack of bright tones and cheesy distortion (check out my review on the Axe-FX). If it were stolen I would probably upgrade to the ME-80 or something, I wouldn't rebuy it solely because there are better units in its own series.
I love the ease of use, the value you get for the price, and the incredibly tone you can get from this little thing. The pedal itself feels very analog and doesn't feel cheesy or digital (unless you look for the cheesy digital effects like harmonizers). I wish it didn't have the expression pedal because I don't use it, but others would clearly love to have it. My favourite feature is the on-the-fly tone adjustment with the tone knob. This thing has pretty much everything I wish it had, which is the main reason I bought it.