cayenne,
That does sound high.  I guess it just depends on how close they run to the original Porsche warranty.  I have a B2B from Warranty America that lasts 60 mos, 80,000 miles for $2275.  I bought it in 2006 so they may be higher by now.  I have had several claims and the coverage is fair to ok.  They won't pay a dealer's rate (cap is $100/hr) and they often will cap the # of hours by the Chiltons guide.  Porsche dealers seem to come in at 20% more hours than Chiltons for the same repair.  If you get a warranty online (not from the place that sold the car) you will probably need to locate a good specialist.  That way, your share of the repair will be minimized - maybe even limited to just the deductible.  I find that specialists are more inclined to be flexible on their parts & labor with a warranty than a dealer tech.
Right now my car is having gearbox work done.  For years these cars have just had the boxes replaced when there was a problem, but over time, parts have been made available & the warranty co's are forcing technicians to rebuild the gearbox or have the car towed to AMCO.  I just got approval from the adjuster for the repair, so that's good news - I will prob do the clutch while they're at it & post the cost & experience on the forum when I get my car back.  
I would get a warranty if I were you.  Just shop around and make sure you 
READ it first.  Mine is relatively good, but I don't think anyone is offering a true mirror of the OEM warranty.  
 
