In general, they pretty much have the same basic abilities for creating automations.
There are a few things you can't do as easily or directly in RM that you can do in webCoRE. E.g., string manipulation, as in this example piston I had on SmartThings.
My solution for that on Hubitat has been to use a custom app and a Rule together. The end result is that it works better - the logic in the piston wasn't quite correct.
(the problem with my piston stems from webCoRE ending up being a general programming language, which is one of it's strengths. Ironically, that RM is not a general programming language is one of it's strengths)