Spring reverb purists will say you can't beat the real thing. And for most spring tank pedal emulations I've listened to I would agree. They simply don't have the same amount of drip and responsiveness.
But this tiny pedal is probably one of the, if not the best, spring reverb pedals I've yet encountered. What is even better is you don't have to carry around a heavy old box, it just fits right onto your pedalboard.
The only downside i would mention is that the knobs are very closely positioned and can be a bit fiddly, but that is the compromise you make with small pedals. Otherwise the build and sound quality is top notch.
If you're going for vintage tones at a small size, this is the pedal for you.