Len- I don't mean to lecture or insult you, but putting "cheap" tires on your T5 would be the like wearing $29.99 K-mart shoes with an Armani suit. Get the 129.99 K-mart shoes instead(he,he,he)! Seriously thou: they are very good tires you can get for under $500 installed(including shipping). checkout tirerack.com and see; also since it appears you drive alot of miles, try to get the highest tread wear possible(I believe it's 300 or 400). I'm not familiar with your Potenza, but 18k miles seems low to me. Keep in mind: the higher the speed rating, the lower the thread wear(generally). I would recommend the Dunlops D60 A2 w/jlb(a CR best buy too) and they have a 30k miles tread wear & they are HR or VR rated and should be about $80each now.
On another note, I'm sorry for the local mom & pop tire shops who can't sell for lower prices. I wanted to do business with them but not at $40 more per tire. i'm sure those tires you have now are way cheaper at at online store. I had 5 ultra perfo.(215/45/17s) tires bought, mounted and balanced for $575 total. At my local tire shop it would have been: $750. good luck, BD