Over the years I've played Chromes, La Bella Deep Talkin', TI Jazz Flats and Sadowsky flats.
For thump, I rank order them La Bella, then Sadowsky and Chrome about equal, then TI.
For attack, Sadowsky, TI, Chrome are all pretty close, then Deep Talkin'. To be clear, what I mean by "attack" is quickness of the note to sound...the TI's are funny in that the harmonic character does not create a lot of "ping" on the attack (I think it relates to the mid-range suckout that someone mentioned above), but they do respond quickly and then bloom, as opposed to blooming all the time - it's a pretty unique sound, but if you lean on your bridge pickup it can be surprisingly snarly and pingy.
For brightness, Sadowsky, Chrome, TI, Deep Talkin'.
For righteous old-school fatness, La Bella, Sadowsky, Chrome and TI, but the TI's are not lame if you cultivate a soft touch.
From tightest to loosest, Chrome, Deep Talkin, Sadowsky, TI, with the TI far more flexy than all others.
Slapworthy (for flats, that is)? Sadowsky, Chrome, Deep Talkin, TI.
For string surface, I can't stand the feel of chromes, and new TI's have a tackiness that disappears after a couple of weeks, but the Sadowskys and La Bellas feel good right out of the bag.
Personally, I use the TI's because I like the range of left-hand expression, but actually think the Sadowsky is a better-balanced string in many ways, and am considering going over to them. Right now, I'm just plain addicted to the flexiness of the TI's which works well in some jazz contexts in which I play. For general application, the Sadowskys or La Bellas are probably best. Lots of folks like the Chromes, especially for rock, but for me the string feel and tension don't work, and I had quality control problems with the last set I tried.