I own two domains for my product. event1.io and geteventone.com. I use geteventone.com for the marketing website and event1.io for the actual SaaS. But there are some problems with that such as it being difficult to track users across the two domains and no shared SEO benefits.
The reason for using two? eventOne.com is owned (but unused) by someone. I didn't want to use geteventone.com for the SaaS because it's long (e.g. geteventone.com/michn/inch-19). And I wanted a .com for the marketing site (plus event1.io has a digit 1 which is confusing to say).
My question is, should I just use event1.io for both the marketing site and the SaaS? It isn't .com and it has a digit but maybe those two quirks are better than the downsides of using two? 1Password uses a digit in the domain. They do own the non-digit version as well, though.
event.one is actually available. For $6k. A year. eventOne.io is also owned but unused.