One is a package everything include, gas etc, with 4 laps ticket but its only for 2 hours....
The other one you have the car for either 4 hrs or the day, but nothing included ( gas and laps ticket ).
When I happened to go twice in Germany 2 years ago I rented the TT on each of these trip.
I did a 4hrs the first time and did 8 laps but had to pay extra for the additional km. A lap is about 20km.
The second time I rented for the day expecting to to do at least 10 laps. but on that day the track open up late because they
had a diesel spill from a race car the previous day. The late opening made up for an awful lot of car on track. After the lap you had to wait a few
minutes to just get off the track. So I ended up doing 8 laps again.
I will rent again for 1 day that give more time and km available.
But you didn't answer the question, which car would you choose?
About normal rental since I always went for business I have to used the prefer vendor of the company, it is now National.
Avis is having the Porsche Panamera for rental.
http://www.avis.de/Panamera