Its not very often i put the light on, just for the effect. Last thing a want to do is set up this display just to damage the cards. Have you had a bad experience with lighting on cards mate?
Got the gloss that I ordered yesterday and think it is going to work really well. A word of advice though - keep the doors and windows open if you are going to use it (as advised on the can). It dries more or less in 20 minutes and I think will provide good UV protection!