I built a LOT of horse fencing using a plain ol' drill, I would have to predrill the holes just to get the screws in. Drill, switch tools, drive screw in, stall out with 1/2" to go, , remove, drill again, dead battery, frustration. You know the drill. (Ha! I have to laugh at my own jokes, nobody else does)
I saw them demonstrating some brand (think it was Hilti) impact drivers at Home Despot and my jaw just about hit the floor, they were driving 6" long lag bolts into 2X8's with no stalling. Great tool but oh so expensive.
Got myself a Makita impact driver, so very happy with it. Came with a new drill too and a charger for $200. Wish I'd had one years ago. Easily my favorite tool for work around the house. Drives 3" deck screws (not spax or other kind with a drill end, not coated, just regular deck screws) with no stalling even into seasoned high quality lumber. Goes like a knife into butter into the cheap fir new stuff they call lumber around here.
That being said, I do predrill holes if I'm near the end of the board or if alignment is important. Just built a quail coop out of 2X3's and plywood, predrilled most holes so they line up perfectly.