Hi,
From an electricians point of view I would go the electrical PVC route. Will not corrode anywhere and easy to make wether tight. Also 99% of the time I always install the size lager then I really need. Pip will be a little stronger as well as giving you room for changes you may make down the road. If you install the smallest pipe you can get away with and down the road you want to add wires you will also have to change out the pipe to a larger size.
Up-sizing your pipe from the start is easy and the difference in price is small.