I've never been impressed with the bailers. I have bilge pumps in both of my skis. The 96XP had one in it when I bought it, I think it was factory installed. I added one to the 96GTI, a Rule 500 PWC, it was an easy installation, just wired it directly to the battery, with a fuse and a switch. The 96XP was wired to only be on when the ski was running, I changed it to be connected to the battery also.
I leave my skis in the water usually for up to two weeks at a time. I have solar battery maintainers that I use and the batteries have always stayed charged.
I spent somewhere between 50-60, pretty cheap insurance.
Lou