Mailinator can be pretty hard to use, since so many sites can detect the addresses and block their use.
I've pretty much given up on it, and use Fastmail's very easy aliasing features with my domain. It's not quite as private, but it's a lot more reliable.
If I recall correctly, mailinator lets you host your own DNS record that sends mail to them. While I have never had any problems, back in the day I had nospam.jrock.us forward to mailinator and that worked every time.
The truly clever programmer could open an SMTP session to the mail exchangers specified in your email address, and reject you because they point to mailinator. I know of 0 programmers in the world that have written this code. I think you could ask the vast majority of programmers that work with email addresses and dark patterns to do this, and they wouldn't even know how. So you're probably pretty safe.
I use mailinator all the time and I have never had a problem, however, which is why I don't even have the MX records to host my own anymore.
> If I recall correctly, mailinator lets you host your own DNS record that sends mail to them.
While I'm sure that works. The main reason I'd use mailinator is for privacy (i.e. not exposing anything associated to me). If I have to use my domain, rather than their free ones, I'm still identifying my domain, so I might as well use my own aliases with my own mail system.
Domains are cheap, and mailinator really ought to register and discard a bunch of $1 specials on a regular basis.
Mailinator can be pretty hard to use, since so many sites can detect the addresses and block their use.
I've pretty much given up on it, and use Fastmail's very easy aliasing features with my domain. It's not quite as private, but it's a lot more reliable.