Based upon the OP's review, plus all the glowing reports here (pun intended) I bought a Cygolite Hotshot 150. I plan to use for the firstbtime this weekend.

The Hotshot replaces a battery powered taillight. So I have no experience with rechargeable taillights.

What are the various runtimes based on the flash mode chosen? Which flas mode provides the longest run time?

Thanks for your help.