Yep, Yahoo has its pros and cons. I host two business sites there and have never had down time that I know of. I have also installed gallery etc.
I absolutely do not trust their one click type install (I do not trust Fantastico either by the way).
If you self install on Yahoo and require really solid email Yahoo is fine in my opinion. Plus they have the financial strength to not make me worry at night about a couple of gigas of data they have of mine.
You should know that their phone and email support is NOT good at all.
Because I read so much about this I signed up for A Small Orange account ($15 for 6 months). I have installed two blogs, 3 survey software and other stuff and an additional 2 add on domains. So I am hosting three websites there now. I have tried everything I know to break it and have failed.
Once when I thought I had an issue I contacted (sunday)their email support and they replied in 30 mins. We had several exchanges and I did not reply to the last. THEY sent me a reminder to check if my problem was solved!!