I have been into RC boats for over 10 years, I am sorry but you get what you pay for. Any ready to run that claims 25 mph and costs less than $500.00 will result a waste of money. If the add says 25 MPH, divide it by 4 for the actual real speed. I have a 40" cat with a 23cc two stroke engine at 12,000 rpm that does 26 MPH, total cost of materials for me to build this from parts was about $800.00 I am not slamming the advertersizer as all these "plastic" boats claim outragous speeds because the average guy has no way to verify them, I use a small hand held GPS on mine and the boat has to be big enough for the weight of the GPS to not affect the speed. I verify RPM with a very light weight two stroke rpm meter that has a lead that raps around the spark plug wire. Your best bang for speed is a nitro like ProBoat's 1/12 scale hydro, I believe it does about 30 to 35 mph. You will need to throw away the prop that comes in the kit and get one that is sharpened and balanced by a pro (bonze or ss is what I use). The ProBoat 1/12 sells for about $350.00. If you want to go faster than 35 you will need to either build it yourself or you will need to buy a custom rig by one of the good builders such as warehouse hobbies, bonzi boats, etc. As for really fast electrics, the best ones use the brushless motors that cost about $300 just for the motor, then you need the cells, high amp speed control that is water cooled, good fiberglass or carbon fiber hull, radio gear, and running gear with pro-polished sharpened prop.