I'm giving MaxSnap 5 stars simply because of the ability to press a key combo and have your next mouse movement move or resize a window, even a background window, without making it foreground.
No need to click, or to use the Title bar (for the move) or the edges or corners (for the resize).
This is a game changer for me.
For now, I use Moom alongside MaxSnap but only as Moom has no prescribed window positions but allows custom ones instead. I know the MaxSnap dev is thinking about also offering custom size/locations too and it already offers many predefined ones that would likely suit most, me too if I weren't so used to Moom's custom option.
I purchased the Beta and so got a big discount.
I found this app via Command-Tab Plus (same dev, I also use that app ^_^)
PS: Dev is responsive too.