Sun protective tops

Does anyone use 'sun protective' tops for running in? Maybe not needed in the UK but I'm thinking it's about time I started using them at least for long runs (virtually on the equator) and would like some recommendations if anyone has experience of them. Looking for long sleeves and preferably a high neck/collar - since my neck and arms are the most sun-affected - but that looks like an impossible combo - most I've seen advertised claim to be sun-protective but then say they will "keep you warm on cool days". We don't have cool days and I definitely don't want to be kept warm.

Thanks for any ideas.

Raidlight make loads of Marathon des Sables kit so they might be a good brand to look at:

http://www.raidlight.com/en/354-desert-races

Thanks, the desert top does look interesting but it's only in a men's version and judging by the size chart even the S would swamp me. Their only women's tops are winter ones. Do women not do the MdS?!!

apparently (and you might want to do more research on this!) cotton is good in warm temperatures. Usually not good at all as a bselayer, it is supposed to offer good sun protection and be better in hotter climates.....

There used to be a quite active MdS forum. I've not looked at it for years but it might be worth posting there for help if its still active Latege

The only forum I can find is only open to participants in the race. You don't happen to still have the exact Web address?

As I understand it, it's much more to do with the closeness of the weave than the fabric (as well as colour and other things). Closely woven cotton works well but it's heavy. Still, if I found a good cotton top that wouldn't chafe, I would consider it - closest yet are long-sleeved polo/golf shirts, but I'm concerned how much they will chafe when they are soaked in sweat with 20-30 miles still to go.