What's the best product to get finger marks off? I was thinking of using the lens cleaner and type of cloth I use for cleaning spectacles.

Yes, that works or the anti-static cleaning wipes you can get for computer monitor/iPad screens (its what I use). Example below (other brands available )

 

http://www.amazon.co.uk/office-products/dp/B00NR0PIYI/ref=sr_1_4?s=electronics&ie=UTF8&qid=1439807128&sr=1-4&keywords=anti+static+wipes