On my second bottle of T400. First ever order(ed) from napsgear. I am sensitive to PIP with things like propionate - it's terrible for me. Have not used it since the Tornel/Brovel days in my 20s(yes - I'm a long time old guy @46yrs).
I heat the T400 under running water by running it over the loaded 1mL syringe after loading it and just before injecting. I dry it off with a fresh paper towel to avoud any excess bacteria from something likely to be less sanitary like a bathroom towel.
I also use filter needles to extract the T (filters down to 40 microns which includes some but not all types of bacteria...most particulates not visible to the human eye are filtered by it). I have levels of PIP between a 1-2 on a 10 scale, but most of the time it's virtually zero. I also have near zero PIP with various brands of sustanon using this technique (filter needles to extract, running the syringe under hot water,dry off with paper towel). I use a 25G X 1" pin for the actual injection.
Lastly - my thighs are extremely sensitive and the only area that I have ever gotten (non infected) abscesses from injections(again - way back in my 20s). I typically inject classic upper outter glute medius areas and or middle and or side deltoids. I'm a fairly sizeable veteran monkey at this point - though nowhere near freaky in our niche world of physique: 245 and 5'8 reasonably lean with visible though blurry abs, my 19" arms are enough to force my shoulders to have to carry enough surface area mass to yield separate injection sites - lol. Try the technique and see if it helps with the PIP.
The filter needles are definitely pricey but well worth it in my opinion(about $65-$75 bucks per 100 depending on where you find them). Lastly, I could be mistaken but I don't believe anyone mentioned the obvious - combing the potent, multi-ester T with a PIP-benign product such as nandrolone or boldenone(or whatever is not problematic for you personally). For example - the first bunch of times taking the T400 from naps - I loaded just 1/2mL and 1.0mL of 100mg isocaproate to dilute the strength per volume. Keep in mind though - I am a fairly advanced user so the 350-400mg dose in a single injection is something I have slowly become used to at this point when taking larger doses. But suffice to say - hardly any PIP by doing so. You could also just half the shot of not mixing with any other product - 1/2mL of the high dosed T-multi ester product, 2x per week. Good luck and hope some of this helps you, and or someone reading it.