i love a good CUP as much as the next guy but.......
for the sake of a few D.E/track days whatever; having to trailer the car, store the car, wrench the car and crew the car on occasion will take its toll on you and become more work then play.
If you also mess up the sequential box it is 25k.
This is why porsche make the "clubsport" RS in europe. For those looking to have a decent track car that can also be easy to own/street legal. It is the best of both worlds.
Since you already have a "clubsport" RS, you can decide how much further you wish to push the envelope by further stripping the car if you really want to go faster. (light weight doors, interior etc.)
With a stripper .2RS you can run with 996 CUPs until the tires fall off.... the 3.8RS will go down in the history books as one of the best 6 speed p-car street strippers of all time. You will see a lot of these RS models at tracks in 20 years. Fully stripped and on trailers.
in 2013, when the 991 GT3 takes the flag as the faster/better Porsche you can then either completely strip the RS and run PCA stock L class as a racer etc., or sell it because you will be bored of D.E in the car by then and will want to upgrade to 991 GT3 if it indeed is really all that and a bag of chips.
Now, that being said, by the time 2013 rolls around you may actually want to sell the RS track trainer and buy a 991 CUP to taste a little racing. Keep the spyder as a collector/toy porsche, as all CUP racers should have at least one old street Porsche to hold in the garage to remember their roots..