I know Wakejunky likes the 4 pump ballast, I like my two pump ballast because it is so simple. I don't like the drain/fill options but I don't want to change the stock appearance, I'm just like that. I will dig into the wiring harness one day and figure out which wires to splice to put in a toggle switch.
In the mean time, I need to make it reliable and MUCH faster. First thing will be to replace the stock .5" solenoid valves with 1" ones. There are two valves, see the ballast and tower owners manual for details. Space is really limited so I'll probably stay with Rule 1100's in the stock location, I have had really good luck with them. One thing to check, the bases can crack and cause priming problems. They also had a recall on those pumps for base screws that would loosen and cause the same priming problem. The fix is to use blue locktite. If a pump is cracked, I will consider putting bigger pumps in. I just wakeboard right now so I just want reliable, relatively quick fill and drain. It takes me a while to put the boards up and get my sheot put away:) I know that the pump should be able to fill the ballast in 4.34 minutes with no restrictions, so if it's double that with the bigger solenoid valves, I'm fine with that.
I think my main problem is sticky valves. The little piston inside gets rusty. You can take it apart and clean it up, but it's hard to do while installed without breaking fittings. I will take my old valves and clean them up and recycle all parts for the back sacks, which are recycled from Shamu 1.