Peach seed carrier oil is potentially inflammatory, I'd really have to try out some Balkan for myself to know whether it'd work for me, whereas with real pharma (using castor or sesame oils), I know for sure what I'm getting will not cause issues.
With Bayer Pakistan Testoviron (castor oil), I can literally inject 0.4mL subQ without PIP. Simply not possible from any UGL I've tried! At best, great UGL like ColonialLabs' grapeseed oil, I can only handle 0.25mL.
Most guys do IM exclusively, which as long as it's an organic carrier oil, has never been issues for me in my delt with quantities as high as 0.6mL. But, I run a high-dose "TRT" and rotate between IM delts and subQ.