I am using a similar approach. However you need to have your own domain.
I make up email addresses on the fly (anything before the @) and use the catch all functionality of my web host to forward these to my actual email address, e.g. spline@domainname.topleveldomain.
I can only recommend it.
I used it to politely ask the one or another company, how it can be that I receive unsolicited emails on an email address when it was created for exclusive use with them and not used anywhere else… and it is really handy for defining spam filters.