wtb new set slicks

looking to try buy a set of new or used slicks that can trust being good;;where would be to buy at lowest price?or would settle for used ones maybe;;can't afford new but have had bad experiance 2 times not buying new;;got one set that was new but was so hard and dried out was told they be unsafe to use;;got a second set that was only to have 10 runs but the side walls all dry rout cracks all over them and was told if can see X patterns ontread side of tire then they wasn't usable;;can see X very much so on them..if i'm looking i will only get to take car out 2 to 3 more times this season;;found a set a racer has[got headers from him and he was very honest on them]anyway back to his tires;;talked 2 weeks ago and he was taking his off and putting new on;;said sell his for $300[hossiers 34.5x17x16]with roughly 20 runs and he got them new in April;;what you think on them..go for it or wait and try get new and be done with it.?