Congrats on the choice Dave. At least two TM members have driven the KH WRP4 conversions on both manual and auto Plus Fours.
Here is a write up of test on what might now be your car, if you haven't read already. It's also in the latest copy of Miscellany magazine.
Unless the exchange spec has changed you lose some functions with their metal wiper stalk conversion, the variable delayed wipe I believe which I for one would not be without.