I got the two point version as the tank is a regular shape and the level should be fairly linear. The five point version is better for odd shaped tanks where the volume of the fuel would not be very linear with the level...
And from experience with a few capacitance systems (RV's and Lancair's) and many of the standard Vans float systems, I would strongly urge you to stick with the Vans Float system.
In terms of accuracy in flight I have achieved better results with the floats too.