I wasn't nuts about the high cost of what is basically a simple, molded rubber wedge. But with that said, this ramp does very well with my manual wheelchair on an apartment, front-door threshold. A threshold height I'd say is taller than most apartments I've lived previously. This reached it well enough. Traction is good. Know that I was surprised by its weight -- as in it being heavier than I expected. But once it was in place, that was a good thing. It hasn't budged since on the concrete slab. In no way would I need to use those recessed, bolt-down ports. It does fine as is.
Dominick 
