I've also used them with no problems and good results. There is absolutely no evidence to back up the frequent claims I see that his stuff is made in a "bathtub" or produced in otherwise unsanitary conditions.
Yes, some of his gear leaves sore lumps, for that reason I will probably not use his tren again, but there is no doubt that it is real. It is well known that he uses a lot of alcohol for sterility. His cyp is leaves less soreness than sustenon, and his eq and deca are painless.
I can't recall ever seeing anyone complain of an infection or abcess from IP's gear. On the other hand, I have seen plenty of those threads about ttokkyo and other brands.
I have seen a lot of vague complaints, but keep one thing in mind. I have no doubt that some of the people (not all by any means) that bash IP are doing so because they are a source or are close to a source. Nobody can compete with IP's prices. Therefore, they defame him and his products.
This kind of unfounded propeganda is especially troubling on this board, where IP is not allowed to respond to it.