Hi just about to order a new board (currently riding an 11'2 buy 30" starboard) Im 6'3 and weigh 110 kilos looking at a 10'5 starboard drive or a 10' whopper not sure if i should go for less volume or stick with this size ( been surfing for 20 years)

I reckon you will be just fine on the Whopper.
Ericson might be able to give you some feedback. He is about your weight and height and rides one.
If you have been using an 11'2 and have been surfing for 20 years you will be surprised at how well the Whopper surfs. Ive seen Ericson throw that board around in waves from knee high to well over head.
Mike Galvin also knows how this board works

Demo the Drive before you order anything

go the element you will be fine

Hi

If you like to surf try 9 or 9 8 Angulo Surfa

I have no affilaition just have been testing them and definitely worth a go.

I am close to a decision

Test the drive if you can, both would work but if your not struggling with the your current board ,ide say the drive would be great for you .