I like Foxgear effects pedals - I already own the Echosex, which is a very sophisticated tape-style delay and very affordable.
With the Rainbow Reverb, we have something which is an electronics product of quality, attractively presented and equally enjoyable to use. There are enough knobs to achieve control of the variations of reverb on tap. However, the range of effects on offer could be described as misdescribed.
There are five effects to choose from, even though there are seven colours in the rainbow spectrum.
• The Spring setting does not sound very authentic, but makes for a good spacious Room effect
• The Church could be a Hall growing into some bigger space.
• The Rotary does not rotate very convincingly, and might be better understood as a generic reverb with modulation.
• The Celestial and Shimmer are twins, and seem only to differ by virtue of subtle harmonic variations in the pitch of the organ / string additions.
To my way of thinking Spring is a popular effect and worth a better algorithm; Room-Hall-Church-Cathedral are all variations of the same thing; Shimmer can come at you in many guises, but in the end you sense the effect more than listen to it purposefully.
Anyway, I still like the pedal for the quality of reverb produced, but the selections may need reviewing for the next upgrade.