UPDATE:
I'm intentionally responding to this old thread because there isn't much discussion of this pedal as per a forum search.
I got the FRV-1 '63 Fender Reverb pedal for Christmas, and I am frankly blown away it. I play a fair amount of surf, and I also like using reverb on some slow non-surf numbers to fill out the sound.
I've tried three or four other pedals, and this one absolutely does a better job of capturing the sound of a Fender reverb tank than anything else I've ever heard. It won't do the "splat" or "crash" caused by kicking a real spring tank, becuse it has no springs. But short of that, it WILL give you the Fender tank sound. I have replaced my Tech 21 Boost RVB with this pedal, and that was the best pedal I'd found before this.
One review of this pedal made a good point: It is a good 1963 tank reverb sound, but not an acoustically accurate reverb. In today's world we have plenty of sound field emulation and there are pedals that will give you an echo that sounds like a real acoustic environment. That is NOT what this pedal does.
This pedal gives you the totally made-up, vintage 50's and 60's tank reverb sound; it's one that Fender invented. It sounds like reverbs of that era, which is a specific and distinctive sound. If that's what you want, then this pedal is well worth your money. If you want a realistic acoustically accurate modern reverb sound, this is not your pedal.
And if you play surf, then you practically can't live without this pedal!