My HP41CV just arrived. Cleaning tips?

[Trond]

Hi again everyone!
I just received my first 41C (of any kind) specifically HP 41CV. My feelings are a bit mixed about the condition: at first I thought I had to send it back because some of the keys (notably the Enter key) seemed to stick. The Enter key took a moment to come fully back out the first time I pressed it. BUT it seems to get better the more I press it. I wonder if the packaging materials were pressing the buttons down in shipping. On the other hand, there are no scratches or dents at all. It feels solid. It seems to work as it should. It also came with three books (Owner's manual, opersting manual, standard applications) plus calc pouch with zipper all for a little over $200.

I still think the unit feels a bit......dirty. Any cleaning tips here?