Price paid: $ 500
Purchased from: PB
Ease of Use — 5
There are a few buttons, a knob and a tiny dual phrase screen... It is not made for on stage tweaking (you are going to scroll forever to get to your delay section). You have to tweak your sound and make your patches before a gig. Luckily Boss has a application, Boss Tone Central, which enables you to easily make sounds on your PC while the pedal is connected. And it is definitely easier on the PC than the pedal itself. Especially when you get to the synth parameters.
As a guitar player I was quite lost at first because I had no knowledge of synth parameters and the new terminology... So it has a steep learning curve for the traditional guitarist. The manual explained it quite well. The GK-3 which is connected on the guitar is quite useful as you can go through patches by pushing the up or down button on it. So you don't have to step on the foot switches to change patches. Each foot switch can also be assigned to activate different parameters and even the GK's buttons can be assigned to do different things. Overall I would have liked to see this pedal with more knobs.
Sound — 9
The first time I saw this pedal on YouTube, I was quite skeptical. It was like a smaller version of the Roland GR-55. But when I tried it out, I was completely blown away by the GK features. The fact that you could combine pure top of the range synthesizer sounds with your guitar(rig) signal was mind blowing.
The pedal overall has a great variety of effects which is almost suitable for any genre. On the normal side, it has the good sounding standard Boss multi-fx like the GT-100. But... on the GK pickup side of the pedal you have a synthesizer with 9 TABS of parameters that you can play with to make almost any sound you desire. It also has extremely realistic acoustic simulators, bass guitar sims, sitar sound, banjo sim, 12-sting sims, COSM amp sims and you can change the tuning of your guitar with the push of a button (without physically tuning it). So it is quite handy if you use different instruments during a gig.
Overall the sound is really good. The only problem with the sound is that the pedal has a full range of sound on some patches. But a guitar amp is mainly mid frequency so you might not get everything you want out of your guitar amp. Overall it has so much versatility. With this pedal alone you can produce a movie backtrack.
Reliability & Durability — 9
This pedal is pretty solid like most Boss multi-fx pedals. It has a metal casing and plastic buttons. It also has some nice weight to it so it does not feel cheap when you hold it. The pedal is smaller than most Boss multi-fx units and can easily fit into a gig bag. I own this pedal now for about 6 months and it still works like the day I got it. It will maybe get a few scratches here and there in a few years but I have no doubt that it will still be in working condition. I feel I can definitely depend on this pedal and it will definitely survive on a stage. The GP-10 also has on/off switch on the back which I found to be much better than the "jack switch."
Overall Impression — 8
I play rock, blues, funk, indie, psychedelic, surf, ambient and I can see this pedal having a spot in each and every one of those genres. It is definitely capable but its functionality fits more a psychedelic, ambient, experimental side. I would not buy this pedal for the traditional multi-fx side. If you buy this pedal it should be for the GK functionality and because you love Synthesizers and other instrument emulations ON YOUR GUITAR. If you don't buy it for the GK setting. It is going to be a very standard, overpriced, limited multi-effects board. At the moment I use it with my Boss ME-70. This allows me to have full control over my guitar sound... And then the GP-10 only works with the GK-3 pickup which controls my synth and other different non guitar effects. Together they work very well.
A cool feature that the pedal also offers is that you can use your guitar as a MIDI controller. In other words if you have a piano VST on your DAW, you can play piano on your guitar. And it works very well and it is extremely fun because it made me play piano like a boss.
I would buy something similar if it got stolen. Probably look into buying the GR-55. If I could improve this pedal.. I would add a looper, more knobs on the GK-3 to change more parameters on the spot and a arpeggiator for the synth section. I would also add more instrument emulations similar to that of the Roland GR-55. Overall I think the concept of this pedal is amazing because it enables guitar players to engage with synthesizers... which is used in almost every mainstream song today and it gives you that extra function in the band.