Not in my opinion.
As far as regulators go, is the savings in weight and corrosion protection worth the premium to the price while sacrificing some of the safety when it comes to higher O2 levels? Sure, you can make them )2 clean, but still... Besides, I can't think of very many people who have said, "Man, this kit is just too heavy, if only I had that titanium regulator to bring some of this weight down!" But hey, that person may be out there.
I think titanium knives are a little less than to be desired also... while they hold an edge well, they are too brittle to use as a pry tool like you could with a SS knife (I'm not talking about prying off portholes either).
And for a backplate? Wow, that would be pretty expensive. Again, unless you do a lot of traveling and/or you have <8% body fat, you would need some of that weight a SS or even Aluminum BP would give you.
Bragging rights are fine (I recently sold my titanium knife on e-bay for the same price as 15 Betty Crocker Dive Knives), but the high price for an exotic metal just isn't worth it for me.