2_95_SL750's

I just picked up two sl750's because the price was right and i couldnt pass it up. I took them out for the first time this last weekend. the guy ran them hooked to a hose before i got them so i thought everything was fine. when i put them in the water, one of them acted like a car in limp mode. it would turn on and run but would not go over 10mph. The fuse for the screen had blown so i just thought that that was the problem but i want to make sure. I dont think that these have limp modes but im not sure on that. Any ideas? The other one ran great once it was running but sometimes had a hard time starting which i wasn't sure about, it also did not have any power in corners. It would fly going in a straight line but when you turned it would bog down until you when straight again. could it just be bad gas? I plan to take them in to a shop to be tested and tuned this week because i want to make sure that i have two good skis before i put money into making them better. thanks for the help.