I'm happy with my WR Long 3rd functions and would consider any of The alternatives. YMMV.
They are the best kit for adding a dedicated electric 3rd function, and is what I just used for my tractor. I care more about quality than product source, but I was disappointed to see that WR Long is now shipping their kits with Chinese hoses. They appear to be good quality hoses, so I'm pretty confident they will hold up okay.
I just don't consider running off the rear remotes or using a diverter valve as a "cheap" alternative. I think it is just a matter of what works best for a given situation.
In my situation, I can foresee myself in scenarios where I need to have a choice of either curl or lift (or perhaps both) at the same time as activating the grapple. Diverting either of those functions isn't really an option.
There are lots of "weekend warriors" that never use more than one function at a time, so a diverter is the best solution for them.
There are also a group of folk that want to run hydraulic motors on the front, such as post hole augers, or those that simply have their rear port control within easy reach of the loader control, and simply routing some hoses under the deck from the rear is their best possible scenario. The WR Long 3rd function, as well as all of the other electric/hydraulic 3rd function and diverter valves I know of state they will burn up if running hydraulic motors and should only be used for momentary operation of a hydraulic cylinder.
Also in my situation, I will have both; my WR Long 3rd function, as well as hoses from my rear ports. Hoses from the rear ports will go to the location of my WR Long valve and have quick disconnects. I will be able to disconnect the hoses that run to the front of the loader at the WR Long valve and connect them to the hoses from the rear so it will be the rear ports sending fluid to the front of the loader. I plan on doing this so I can run hydraulic motors on the front of the tractor.