The previous answer I gave was from what I read on forums but I think you may need an expert sharpeners opinion if there is any advantage of the 5 degree angle on your reel mower for longevity.
The manufacturers recommendations on reel sharpening is what you would normally do to sharpen the reel.
Some reels have relief angles that maintain a better longer lasting cutting edge that require less grinding intervals.
I have seen some people say a lathe is better for sharpening the reel and may be a lot cheaper as I heard a guy on this forum had a reel sharpened for $55. in 2013 at a sharpening machine shop.
Video of Lathe sharpening below. [video:youtube] [/video]
