OK, If we split hairs, yes, you will have a deviation on an hotted up engine, and if you have an true temp. output, you will find that he temp fly's up on piston fire, and cool's down on fuel intake, cools when going under a tunnel, and heats when in full sun.
These are things that the normal VW aircooled guy has very little use for. If you have a normal or slight mod air cooled, and you measure the oil temp. you will find the average effect that the oil gives to a temp. meter reassuring, as one does not want to have a hart attach every time you hit the gas.
You will see the temp clime on hills and drop down hill, you will even spot well in time if the fan belt breaks,
So Yes, for the boy racer that wants a aircraft cockpit of gauges, then yes, go for it, but the normal guy like SEAN, oil temp. will serve you well.
If your seat has been fitted correctly, it will not come out on heat. Your oil will fry before the guide comes out.
Your engine can take more heat then your oil can before causing damage.
once again, only my opinion, and not wanting to start a bun fight.
I bow out.....
Herman