If you need a workstation, I wouldn't recommend a Pi unless you needed something basic for a kid or a parent. In almost all cases I'd recommend a real PC.
I would recommend a Pi for a workstation if someone wanted to tinker. They could build circuits they could interact with or play around with Linux.
But if the only purpose is a workstation, a Pi wouldn't be high on my list.
If grandma just wanted email and Facebook, it isn't really a bad option.