[Perfectlap]

look at the fine print. Their lawyers go through this with the jeweler's loupe and usually demand that you not miss a single scheduled maintance by even a day or they'll deny the claim. "all work must be done by a certified mechanic" bla bla..in other words no DIY maintenance. Usually. They have to throw up as many road blocks in paying out a catastrophic failure as possible. i doubt they will require the work be done at a Porsche dealer but I doubt an "approved" shop is going to charge you the same book rates as Toyota. Also, hourly rates for some Porsche specialits is not that much lower than the dealer rate. I don't go to those.
Also, I believe one forum member (Navarro?) had to take a well known insurer (Warranty Direct?) to Court in order for them to pay up. I think they had some argument about the oil not getting changed frequently enough.

p.s.
I don't think I've ever heard of someone on here reporting theat their after market warranty covered the cost of their blown engine. ever. 9 times out of 10 it's Porsche good will or the owner has to eat the new engine cost.