It really all depends on your budget, where you want to ride, and what kind of riding you will do. Kawasaki, Yamaha, and Seadoo all make great machines and they are priced anywhere from $8,000 to $18,000 with the exception of the Spark which you can buy a basic one for $5,000.
Here are my thoughts:
Seadoo - Tends to be the most sophisticated with most bells and whistles. All their machines use a closed loop which is nice if on the ocean. Very cool looking if you like their style or ugly if you do not.
Yamaha - The only manufacturer to to have a dedicated only marine motor. IMO, the 1800 motor NON super-charged is probably the best set-up and the FXHO is probably the best machine. Will set you back about 13k with a trailer. They have three motors. An 1100, an 1800 and an 1800 with a SC.
Kawasaki - The least talked about, but the best diamond in the rough if you ask me. The STX-15F is by far the best machine on the water for the money....PERIOD. It lists at 10k, but you can buy them for $8,000, or less. Kawis have the smallest part of the market (about 15%). They have ONE motor which is the Ninja bike motor and makes 160 hp. It will never break. They also have a 310 hp SC version. The STX is small on bells and whistles but a great handling machine and will go mid 60's. BUT, it is light on creature comforts.
If you want to compare near entry-level machines, look at the Yam VX Cruiser, the Seadoo 35 or 155 and the Kawasaki STX or the Ultra LX (non SC).
I am not a fan of SC models. You get better acceleration but poor MPG and more maint.
resale is much higher on non SC models.