You can retrofit that Twist-N-Lock pump onto your current head, if your current head is a Jabsco.
These heads are pretty much the low end of the indusrty.
I have one on board our boat and we replace either the entire head or the pump assembly every few years. Sometimes its just as cost effective to replace the entire head. Following your link the head is $140.00, The pump alone is right around $100.00. So the parts are more expensive than the complete head. Go figure??
The other thing that goes is the joker valve.
get used to it, or replace it with a better head.
When working and all new, I have no problems with them, just that they don't last long.
Courtney is My Hero
If a man is to be obsessed by something, I suppose a boat is as good as anything, perhaps a bit better than most - E.B. White