We didn't bother with stairgates for our last two, but we did for our precious first few.
The cheap ones with the bar across the bottom and pressure fixings were not good. The bar was a liability and the pressure fixing wrecked your walls. I've even seen them go through plasterboard in people's houses. The level clasp was annoying to use that you'd tend to just leave it open.
The kind that we could live with was a wooden gate that you fixed with screws and rawplugs into the wall, and the same with the clasp on the opposite wall (or newelpost).
I don't think a spring loaded one is good for the top of the stairs, but I have used one at the bottom for when we had visiting children who didn't understand the word no.