I have a 25 Daytona and have had many Tournament ski boats. Obviously, the tournament boats are much better at towing skiers no matter what they are riding. I did, however, teach my 10 yo nephew to ski behind my Daytona last summer. He got up on the third try and never had a problem. I do have a 90 foot Barefoot skiing rope but with him we just used 75 feet of it because his weight did not require much speed to keep him on plane.
I have skied behind my boat as have a few others and have done just fine. The wakes take a little getting used to (the tunnel). My son even wakeboards behind it when he can't get a pull form a tournament boat. But for the most part we just ride in our Daytona and occassionally pull a tube for the little kids.
Long and short answer....you can ski behind a 25 Daytona, but don't buy one if you plan on skiing a lot. There are better boats for this activity. Oh yea, mine has a stock 502mpi with a bravo I. No problems planing even pulling skiers.
Rick