They are entirely different boats. One is not necessarely better than the other. The Perry boat is a Freeport
and a great cruiser. The Gurney boat is more of a racer/cruiser. Freeport
is beamier, heavier and carries more sail. The Gurney boat is potentially faster. However the Freeport is no slouch, I owned one for a bit. The layouts are very different however have the same feel since they came from the same builder
The cockpits are different and the Freeport has a drop down transom.
Islander 36's are common and relatively cheap
. Freeports are much less common and more expensive.
Also, the freeport has encapsulated ballast, the I36 has external cast iron.
That's just a start