I am running a titanium catback exhaust and the stainless steel GReddy/Trust downpipe which has about the same design as this Autobahn one and I like my setup very much!
This Autobahn one seems to be a copy of the Trust one I have, just being titanium and therefore even lighter than the stainless one, which is good.
Also the size is the same being 2.5" and 3" so no difference here either. Gaskets will be interchangeable too then as they have the same flange looking at the pic.
Only thing I can not comment on is the fitment quality of the Autobahn downpipe as I haven´t tried it. But I doubt it will be too bad to be fitted. It might not be 100% snug glove fit like HKS, Trust, etc but will be ok to fit I´m sure. I have tried their FMIC and their oil coolers on a few cars and they were all ok.
Keep in mind if you fit titanium exhaust parts you will change the tone of your exhaust as titanium produces a slightly higher pitched noise/frequency. Not particularly bad, you just need to know before fitting it.
To be honest you shouldn´t have showed me this as now I´m tempted to fit it to my GTR. I probably would give it a shot if I hadn´t the Trust one on already.
How much is this one??