Out of all the ones I use the Maine-Anjou site has got to be the worst. I have not really ever been able to find information I was looking for. The office is not long distance for me so I usually just call instead of wasting my time, love the cattle hate the website. I do however think they have a good online registration system.
The Shorthorn website is a lot slower than the others due to pictures and things, some parts of it are really good and other parts of it are really bad. I hate calling that office, the most unhelpful, snotty people in the purebred business!
I love the Angus website, I have only had to make 1 call to that office, everything you need is on there. They live broadcast most of the bigger shows on there, they put real time placings daily during the majors and such, just a really good site.