Thzis a difficult question for me. I have since I am dealing with type theory closely searched for understanding of every type and nowadays I have a somewhat clear imagination of the differences and strength and weaknesses. I can at least imagine the basic idea.
I'ld probably want to test drive an infp just for the pure egoistical reasons to see how it is for my girlfriend. She must have a keen mind when it comes to combining behavioural patterns of humans and with those instruments to profile the person standing in front of her. I imagine it's like if I am asked to solve a technical problem and then combine different systems and structures with each other to create a new system or to fix a system.
Other than the infp, I would basically be intrested in ip types to test - drive. J types dont really intrest me, since they most often appear to be stuck in some sort of field of expertise and appear to be less flexible. This sounds rather boring. istp's would be very intresting for me aswell, especially one who is actually very practical and has some technical forte. I'ld like to see how he does solve problems practically seemingly easily, while still denieing to do any math at first, yet producing a perfect result