3/8 might be better, look at any guides/pulleys..
...to see if you can fit. Previous owner of my 240 went up to 1/2" for more comfort, but the lines hang up in light air(under 10knts)every time you tack. I went down to 3/8" with the "fuzzy" surface. They are OK, but the 1/2" really is easier on the hands, especially if its blowing. I could have refitted the sheet runs to handle the larger line - but line was on sale and easier. I think you'll like 3/8" just fine.