The Titanium F3 body is quite stronger than the normal F3 body. I have two F3 bodies with the HP finder and one MD4 drive. The F3 body that does the lions share of the work is battered, dented and looks like it has been dragged through a war zone, but it works like the day I bought it.
I have a friend with the same outfit, but one of the bodies is a titanium body.
What is interesting is to see the difference after about 15 years with two bodies side by side in a camera bag.
The F3 bodies are very strong, but the material they are made out of is slightly malleable. That is, they take a bump and the outer shell bends or kinks slightly, they also lose their outer coating of black relatively easily, showing up a brass coloured material underneath. I think the term the English use is, "brassing".
Back to my friend with the two different F3 bodies, the normal one is brassed quite heavily and has knock marks all over. The titanium body is almost mark free and dent free, although it does have some minor dents. Considering some of the knocks I have seen it take, the titanium body is way stronger than the normal body.
The normal or HP finder is not titanium and the MD4 isn't titanium either.
The MD4 is tougher than the F3 body material and is virtually undentable by comparison, if you know what I mean.
I would have an F3T in a flash if one was available, even though I'm not on the market for one.
The best thing about an F3 with a drive attached is that you can carry the camera around very easily, even with very sweaty hands. I road tested an F4 when they came out, was given it for evaluation in fact. I didn't like it as the rounded shape meant that when I was walking around with a 300 or 400 mm lens on, the thing kept slipping out of my sweaty hands, I went back to the F3 before the test period had ended. For what it's worth the F4 is more or less an F3 with an inbuilt drive and autofocus, other than that, they are basically the same thing.
Mick.