I've thinking about purchasing Proton Mail Plus only and just only to have IMAP support, but I've looked all the features that the Proton Unlimited Plan have, and honestly I believe it's worth, but I hate having all the eggs in the same basket.
The features I believe worth the most are the 500GB storage, IMAP support, all the VPN servers with P2P and unlimited SimpleLogin aliases, but when I ask if it is worth the price I mean, the majority of those features I can have them having individually with others services and even at lower price.
I think it’s worth it. I use many of their services and they integrate nicely between each other and between different platforms. Plus, their customer service and tech support are excellent. I’m in the beta program and they’re always super responsive to bug reports and the like.