What is tap tempo for? Is it really needed?

I am trying to decide between boss-dd3 and dd-7. I tried analog delays and are not for me at the moment in my price range (around $150).

My understanding of delay unit is that you play a note an it echoes according to preset length of time and the echo speed (number of echoes) per time frame.

I tried EH memory toy (overloads easily), MXR carbon copy (too dark for my setup, WayHuge AP (good tone, but not to versatile).

Tap tempo let's you set the delay time without using the delay knob. You can get a precise amount of delay in "tempo" with a song. Just tap your foot twice on the switch and the pedal sets the time between your taps as the delay time. The longer you wait between taps = longer delay times.

It's up to you if it tap tempo is really needed. If you need long delays and many repeats to be in sync with the beat (or in a U2 tribute band ) then you could benefit from tap tempo. If you're just doing rockabilly slapback or just use delay for ambiance, then it's not neccesary.

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