The straight and narrow, or the straight and not-quite-as-narrow?

[Mojo]

Ok guys, I think I've pretty much made my choice for my first straight. I've got my eye on the Dovo Special Tortoise, which I hear is a 1/4 hollow ground blade. What I haven't figured out is whether to go with the 5/8 or the 6/8. The price difference is only $4, so that's not a factor. I have a pretty tough beard (a couple of days after a shave, you could use my face as a coarse hone), and I've read a couple of different things on this. I've read that bigger blades tend to be better for tougher beards, but I've also heard that a heavier grind would be more of a factor than blade width.

So my questions are:

1. Is the Special Tortoise really a 1/4 hollow?
2. 5/8 or 6/8?

Either way, it'll be going through Lynn to get honed up. Actually, it's his recommendation that first led me to look at these, and I've seen nothing but praise for them on three different forums. Thanks for any advice you can give me guys!

Joe