If you need a consistent spring reverb that will always travel with you (so that you are not dependent on the built-in reverbs of the amps you play, and want to be foot-controllable), but you do not want to carry a pedalboard unfriendly reverb tank around, this is the best solution. The Danelectro Spring King is not completely analog, as it has a digital pre-delay chip, but it does not matter as long as the sound it produces is very natural and you can actually hear the srings vibrating in the sound coming out of your amp.
The footprint of the pedal is huge, but it has a real spring tank inside, so it is inevitable. The knobs are chicken-head, which makes it easy to control the parameters with your foot between or during songs.
The pedal is not very versatile, as it gets you only 1 type of reverb - spring - but if it is what you are looking for, you won't be disappointed, as it is better than digital any spring emulation in a reasonable price range, and has loads of decay on-tap.
I must admit though that I ended up buying a digital pedal with a smaller footprint and more versatility, though it cannot quite replace the Danelectro. I would still highly recommend this pedal for Spring reverb lovers, especially guitarists playing surf music.