Besides the suction power, what are the differences between them? I know some you can connect to wifi and others have boundary strips
Eufy robovac comparison
Meanwhile there are so many (too many) models around.
Nobody will know.
But you may find a table somewhere at the EUFY-website.
And there are different models offered in different countries 
I’ve looked on the Eufy website and on Amazon along with other places. I see some slim and other have certain features