p.s. the D-TWO does tapping of custom patterns, although i've not investigated this much. you can get the manual off the tc electronic site to read further.
i also have an eventide DSP7000 which is pretty amazing, so if you could pick one of those up second hand it might be worth spending the extra. however, for quick and easy delay i always reach for the D-TWO first.
also if you really want to go into that sort programable tap thing maybe you could still consider going the software route? don't know what DAW you have but logic's designer delay is very good, and also the cheap (but i think excellent) delay plugin from audio damage - extremely customisable: Audio Damage :: Ricochet