I agree that when comparing say, the Eagle GTII to other tires in its class, it is greatly over priced and not worth the extra money. The BFG Radial T/A's and the Firestone tire that is comparable are much cheaper.
The Eagle F1's are a good deal though. They are quite a bit cheaper than the Bridgestone Potenzas and some of the other max performance tires. Although the Kumho Ecsta MX's are even cheaper yet compared to the F1's. A friend of mine just got a set of MX's, looking forward to seeing how he likes them.
I don't know what the price range is on the assurance tires or what the are comparable too. Based on what I have read they sounded like they would be on the pricey side. They may be worth it if they are all GoodYear hypes them to be, but I hane't heard a ton about them yet to really be able to say anything either way.
Former owner of 94 Bird with DOHC 4.6L swapped from a mark VIII
2011 CTS-V Wagon
1968 Torino was an original 289, C4, fully documented numbers matching car. Now: DOHC 4.6L/T-56 swapped, Cobra intake, IMRC delete, BBK long tubes and H pipe. Dynotech Aluminum Driveshaft, 9" rear with TrueTrac and 4.11's.