OK, then I guess what you meant to say was that the Prius restricts acceleration in EV mode to 25mph (I guess, as I said I haven't bothered to play with EV mode yet)?? However, under light load conditions it will run electric-only up to 46mph without spinning the ICE (stealth mode) and under even lighter load conditions it will run faster than 46mph without burning gas, though the ICE will be spinning (warp stealth). All of this helps control the rate of drain of the battery and thus increases its longevity.
First year of any new car model has greater chances of issues, though our 2010 has 29,500 miles on it now and no warranty work or any repairs of any kind yet.
