I have sites using "all of the above", and concur with Owen's comment regarding it being a "personal preference" issue.
RA route learning simply "works", and I (surprisingly) have not yet had problems where the high/med/low settings were not correctly honored (95% Cent/Deb environments, FWIW). FAIR WARNING: You should tune your advertisement interval, valid lifetime, etc. to values appropriate to your environment, as most router defaults I've worked with are quite high. The issue of using FE80::1 everywhere (as the virtual IP in your FHRP of choice) is operationally a wash, in terms of perceived complexity from the front lines. Do people give me quizzical expressions the first time they learn/use it? Absolutely. But a small amount of "getting comfortable" with def.gwy subnet =/= the intentionally provisioned subnet is outweighed by the ease of "oh, it's the same everywhere now." FHRPs gaining the use of global prefixes seems to be coming along nicely across product lines, although not yet universally supported. ...and on the <?!?> front, I'd just as soon use the VRRP virtual MAC + ID formula converted to EUI-64, but the RFC says you're not supposed to. :)
