Using this to tap tempo on a TC Electronics Flashback 2. Realised the polarity wasn't matching the expectations of the TC, but it was very easily fixed by just not plugging the cable in all the way in to the TC. (Found this suggested solution using Google). Actually works like a charm. I was planning to fix this permanently by getting myself another cable between the Tap and the TC that changed the polarity, but the temporary solution works too good so far... :-D
Overall the Tap Tempo switch seems very sturdy and does the job. Not super silent when being pushed, but not more noisy than most other pedals either. For the extremely low price, this piece of hardware delivers much more than you can expect. I wouldn't look elsewhere, unless you wan't a switch that is dead silent (or you have a strange urge to spend more money...).