Hi RickT,
The skater F1 was my first Tunnel 3.5cc. It is a good hull, fiber glass is well made and the design is quite ok. Once you will make the sponsons "True" it will become another boat. Stock you will find a big difference between the right and left sonsons. Work this area and make sharp angles and it will be a fast hull.
Now I am building a Top Speed 2 and let me tell you it is a far better design, bigger, larger and stepped sponsons. Stock, the spnsons of the top speed 2 are already true. Well I would go for a Top Speed 2.
Tony