Good stuff. Works as advertised. The disk space is more eye-candy than it should be, and is confusing at first. Lacks detail even when you figure it out. The Manual Trim feature works, although if you use it on your boot drive, expect two things: 1) a LONG wait (mine took 3 hours) and 2) some scary "out of disk space" messages in the final 20 minutes. Also, when you think it's probably done, it isn't. Running it overnight isn't out of the question.
Also, under the trim tool options, the state of Kext signing is (to my way of thinking) backwards. When it says "Kext signing is off" it really means "Apple is still requiring kext signing" which would be "kext signing is ON" to me. Apparently it's self-referential, and by "signing is OFF" they mean "we have not disabled kext signing, so the feature we have to do that is OFF."
I find that confusing...
However, all that said, quirks and caveats aside, it's working as advertised..