I wouldn't grow hostas in full sun, mainly because they like lots of water and I won't be a slave to my plants :)

However, lots of folks do, for whatever reason. I found that, very generally speaking, light-coloured and variegated hostas can handle sun better than the darker and blue varieties.

Some of my hostas get sun until noon and have much less trouble with snails than those that are in shade.

Some, like Guacamole, for instance, manage sun quite well. You can probably do a search at various hosta sites to find those who are more sun-loving than others.

That said, I have friends who have masses of beautiful, rich-green, solid coloured hostas that right now look good enough to eat. They are in full sun and by July look absolutely pathetic. Still, pathetic or not, they come back every year and put up a good fight. Sad, really.

I have a patriot on the south side of my house in full sun all day. I water it at the same time i water the others, and it does great. It's about three times bigger than some of the other that were planted at the same time. Put them in the sun and let them get big. If they look horible in august, you can always move them.