My 2 cents:
I wouldn't spend that kind of money just to get a better daylight
viewable screen.
I'd upgrade to an 1198 with a large daylight viewable screen, and
a beefier processor. The 1198 has enough power to run all of the
accessories you may want to ad in the future.
You can buy sun shields to attach to your unit, or buy sunscreens
that stick directly onto the screen glass. They will help dramatically.