
Congrats on the new ski. The SHO is a stable, comfortable, reliable, and very fast machine. A little hard on fuel usage if you run it fast, but at least you will be burning regular instead of premium that the other brands have to have. Read the manual on break in procedure before you put in on the water.
You can pull any 2 person tube. They come basically in the sit down variety or the lie on variety. If you have very young riders, I'd go with a "sit in" type of tube. Older kids and teens like the types that you lay on top of. In most states you are limited to the capacity sticker on the ski (3 person) in the case of the SHO = 1 person on the ski and 2 people on the tube, or 2 people on the ski and 1 person on the tube max. Therefore, no use in looking at 3 or 4 person tubes. A very common mistake for a new owner is to run over the rope, which will suck it into the pump and really screw up your entire day (done it myself, towed others that have done it). So get in the habit of always watching the rope, stop the engine when you are not towing, train your riders to manage the rope. Other advice is to make sure the tube is properly inflated. It needs to be rock hard. I see many under inflated tubes at the lake, and they are much harder to tow, will tend to submarine, etc..
Most comfortable vests are the neoprene type. I like the ones that have a zipper in the front in addition to the buckles. Be sure you try them on in a sitting position. If the vest comes down too far it will hit your legs while you ride and get pushed up around your neck. Be sure the arm holes are large enough to allow you to reach the handles without rubbing. Some good brands are Jet Pilot, Hyperlite, O'Neill, there are others..............fit is most important factor.
A "ski" or "PWC" can apply to any brand. "Jet Ski" was actually coined by Kawasaki, so you may get some grief if you call your Yamaha a "Jet Ski". Yamaha calls their skis or PWCs "Waveruners". Therefore you can say my "ski", my "PWC", or my "Waverunner" and be correct, and socially acceptable in the PWC community.