In Mail 4.3-

When sending an email composed with stationery, would all recipients receive (see) the stationery as it is sent, or is that dependent on the ISP, having Mail, or some such?

I think it is dependent on the application used for e-mail. For example, my e-mail client is set for plain text only, so e-mails that are heavily stylized arrive as text with attachments. My application (Powermail) allows me to switch to viewing as HTML either internally or in a browser.

Many thanks, Ira.

That much confirms my opinion, that, in general, Stationery may have a use, but it is unlikely that I'll give it a go.