On a bass gig, the only gadget between bass and amp is my Korg Pitchblack. The batteries last for ages, probably because the current draw is infinitesimal when it's bypassed. It gives you a warning when the battery is dying, and if it does die mid-gig, it defaults to bypassed, so no embarrassing silences.
I have had the original TC Polytune on my big guitar pedalboard since they came out. I use it in strobe mode. The polyphonic mode is ok for quickly working out which string(s) have gone out, but it invariably gives a different result when you go to tune just one string. Also it does create some noise whilst tuning, but this could be because I don't have it running on an isolated power supply.
For all other purposes it's the Snark clip-on. I have 3 secreted in various places!