1) Not that I know of, I have been here for 10 months, maybe someone else who's been around more can confirm, I'm interested too.
2) I don't remember having any downtime during those 10 months, if any happened, it was for very short periods or something.
3) Yeah they know their stuff very well, and reply to tickets very fast, I usually get replies that solve the issue within minutes.
4) I guess I knew your current host, they don't have cPanel right? It would have been easier if they used cPanel, anyway it's still quite easy to trasfer the database and files, download/upload files in FTP, then import the db dump in phpMyAdmin or upload it and open a ticket for the techies to import it, if it's larger than what phpMyAdmn can handle.