I warm all my oils before I draw, draw with 25g 5/8" and inject with 30g 1/2" slin pin for my TRT. I only use 25g to inject on cycle when pushing more oil than a slin pin will hold
Can't believe how many people heat the oil up. Never once have and stuff goes easily through slin pins. Can't imagine the need to heat up a 23g. And it's with high oleic safflower oil (one of the thicker oils).
The time it takes to draw with a 23 or even 25g compared to heating it up and drawing is negligable IMO. Youll waste just as much if not more time heating it.