I believe Suntek (OEM Kodak) is a bit thinner, and installers like it because it conforms to complex shapes more easily.  It also has less visual 'orange peel.'  

XPel seems a bit thicker, and perhaps more durable.  

I have each on different cars, no big preference either way.

On Porsche's I recommend getting the full hood, rocks can still hit up near the hood's trailing edge.  Mid-engined Porsches will need film around the side air intakes, the front tires kick up rocks and the side vents suck them towards the body.

A quality film job is 80% your installer's expertise, so if you trust yours, go with his recommendation, I say.