My family has a server at their home. It's an older spare PC they had sitting around and they host a lot of photos from events happening in the area.

The website itself loads quite quickly because of well managed upload/download limits on the FTP, but every few weeks they have to send emails around with the IP changes and the domain going down temporarily because of it. FTP isn't used much on it at all and they have quite a fast connection, but you can notice it's not hosted in a datacenter and FTP really is crawling.

Not recommended. Like people have already mentioned, keeping a PC up 24/7 costs a lot more than a simple webhosting plan and downtime is frequent. Even if it's just for testing a small personal website, you're better off getting some cheap webhosting to suit your needs.

The only real benefit is the fact that you have complete control over the PC, but that's something you don't need for a website.