You seem to be taking a smart approach to this, I applaud u for that. After seeing ur stats and goals, I have one more question...why sust? Assuming this is ur first cycle, I would strongly recommend leaving the sust alone and using something that is easier to keep levels stable in ur body for this first cycle. A great choice would be cyp or enanthate, (i prefer cyp personally but either would be better in this case as they are very similar). I suggest 500mg cyp/enanthate a week and 300 deca, followed by pct...what do u plan to use for ur pct by the way?
As far as a 22g goes, yes u can use them to draw and pin (glutes, quads) and heating the oils is not necessary. Draw using one tip, switch to a new one and inject...then dispose of both tips and use new ones next time-even drawing tip should be thrown out, needles are too cheap to risk infection...
Good luck, any other ?s let us know!