It's unresponsive, inept, and they seem to have a peculiar mania for keeping you on the phone forever asking you question after question to verify your ownership (after the long wait time).
What did it in for me is that they shut my site off due to an alleged malware detection, but somehow they couldn't tell me what file it was or anything about it.
Yahoo does NOT allow you to cancel a plan unless you CALL them and good luck with that...
Now the only thing that works reliably is my Wordpress blog, but I have to fight my way into it every day, multiple usernames and passwords, etc, and about 1/3 of the time I don't make it.
I'm currently trying to transfer my blog only to Bluehost, but I'm experiencing problems even with that, which I suspect originate at the Yahoo/Aabacco end. I have to echo what other people are saying about the support.
I was happy with Yahoo Small Business for 14 years, but Aabaco, or Luminate, or whatever their name really is, is just a fairly expensive mess of a web host.
Just use 1and1 or another web hosting/domain service.
You'll save yourself time, money, and a lot of aggravation! Their systems have been out of date for a long time, but they used to be reliable.