No, I don't have any studies nor have I seen any. Test suspension is very similar to IGF-1, in that it is immediately able to bind its receptor once injected. Injecting into a particular site will mean a higher ratio of test suspension to AR at that site (with pretty much any other gear, this is meaningless due to the ester being attached). You'll get more test binding ARs in that site due to the high test:AR ratio. You'll hear BBers that swear by test suspension precontest to tweak the physique so to speak
I'm talking site injection with intent...like shooting upwards of 3x/day into the same muscles over the course of 2-4 weks. It's more of a last resort than something you'd do off season.