Re: [exim] What are the options?

Quoting Tony Finch:

>> it won't hurt and it will tell the clueful ones that the spam is not sent by
> It will hurt: you will no longer be able to email a significant proportion
> of the users at many sites.

In theory, maybe, but you'll get notified (as long as nobody's
blackholing). In pratice, I didn't get a single notification of such an
event in the time I have a SPF record published (which was not long
after the SPF introduction, but I don't remember either date).