Hello, I've recently been looking for a new hop up unit (Also a bucking.) I've searched around for a little bit now, just over a week now and I can't seem to decide. I've seen the blue prowin hop up, but that is only the unit without any of the gears you turn to adjust the nub for the hop up to work, also it's a little bit out of my budget. I was looking at the SHS hop up unit for m4/m16 styled guns but sadly couldn't find too many reviews. Anyway, what do you think is the best hop up for under $30?