I've done sub q injects of Sustanon, test e, winstrol depot, trenbolone e... at least.
Absorption rate is supposed to be more stable with sc injects, as a IM inject absorption will wary depending on blood flow.
When just doing 2x1ml a week f. Ex I do everything sub q.
Some are worried about more estrogen buildup with sub q shots, since aromatase is present in fat tissue. This is not my personal experience however, but I don't have that much body fat. (Even though I have too much IMO)
Haven't got any report about increased estrogen by sub q from anyone else either, if someone does then chime in.