grac3923 -- because she really needs a low set stone, the bands all have that bump out under the stone that don't allow a standard band to sit flush. Unfortunately I really don't think she'd like a gap. She's a "neat and clean" style person and I think she needs a fitted/flush band to stay sane.
elf925 -- I'm pretty sure this will be presented during their traditional anniversary dinner with just the two of them. Either that or the boy will be jumping out of his skin wanting to give it to her and he'll put it under her pillow that morning or something. I can see him being too excited to wait. As much as he doesn't get jewelry, he DOES get making the girl's eyes light up. They are such a wonderful couple!