For several years I shot Manual all the time. It became natural, I liked the complete control, and I got very quick at it. But over the past year or two I've switched to shooting Av 90% of the time. Learning to finesse the exposure compensation took a bit of practice, but overall I find it much simpler, and it really does let me focus on shooting more than on the settings.
That said, when the light is funky, or changing rapidly (or I'm shooting studio w/ strobes), I revert back to manual.
(On a side note, I've honestly never once shot in Tv...I still can't figure out when I'd want to...)
. i only shoot in manual when i'm using flash indoors.
.
