They have been very good for several years.
Last September they transitioned to a new and "improved" VDS system that went very badly. Lost data, lost email, broken scripts. Still continued the "conversion" until the support system broke down.
WestHost deleted many, but not all of the threads on their support forums from the time of the conversion fiasco.
From what I can tell, the support is back to the normal good quality. They are not doing any conversions, so the system is stable. They are normally a good value unix host.
Currently, the big problem is that WestHost has VDS on all shared hosting accounts which makes the system very slow. Perl scripts that worked quickly before the conversion now time out.
I would look elsewhere.
I used to be on their old shared service. But after failing to convert me to their new VDS platform after promising to do so, I decided that was it, I had to leave: that was about 8 months after the initial conversion date.
But before I left, I tried their new VDS platform. The service is fine, however, the "site manager" interface is tremendously slow.