Everyone here is either crazy or didn't read the original post. OP clearly stated he's looking for comfort and long tread life. Handling is not his main concern and he's on a tight budget (inferred from his statement about barely able to afford his car). The Michelin PSS DO NOT FIT any of this criteria...
OP for what it's worth I run Continental DWS on my daily driver and I currently have 47k on them. I can easily get another 5k and 10 if I'm lucky. They are by far the most comfortable tires I've had and out lasted my previous set of Michelin A/S (38k). If you don't have snowy conditions during the winter, you can settle for the DW's (D = dry, W = wet, S = snow).
Another thing to keep in mind is 17's will run cheaper than 18" tires. If you can find a buyer for your 18's, you may want to look for an oem or aftermarket set of 17" rims square fitment (equal width front and rear). This will allow you to rotate your tires which will help extend its life.
Also be sure to research aftermarket brake pads. While some may offer low(er) dust as compared to oem, they may squeal more during which is more annoying in my opinion.
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