I'm on TSTs as my every day driver/do everything ski. Like you I was between the TST and the SFB. Absolutely love this ski, and I haven't found anything it can't do. Ripped groomers for the first month and a half of the season because we had no snow and they were perfectly comfortable, then finally got them into some steep trees and pow last weekend and they killed it.
I'll note that I do have a true powder ski that I use for days it really dumps, but if its snowed and Im not sure exactly what the conditions are gonna be up on the mountain, I grab my TSTs.
I would say the JJ, as the powder performance is better than the SFB and can probably carve groomers as well as them, futher the TST is just a slimmed down JJ with no tail rocker