I used to run front / rear TTs before swapping out the D35 for a Rubicon D44.
If it wasn't for my annoyance at having to replace damaged axleshafts twice on the D44 I wouldn't have done the swap. The Truetrac worked great for me for about 7-8 years and I loved them. In some respects, I wish I had a D44 with TT in it out back for the simplicity but I couldn't pass up on the Rubi D44 deal I got. And like Island Tj, I had a lot of incredulous observers swear up and down I was running lockers (pre-axle-swap). The TT's just work and work well. No fuss, no muss, lots of traction, and excellent on-road handling.
Go for the dual Truetracs!