1. Subscription model. I will be willing to pay even $250 for a good email client, that is superior to the native macOS client. If it really adds more features that I need. Meaning, I can use mostly all the email related features offered by Fastmail. But I am not willing to support subscription models.
2. No iOS client. I use email on macOS and iOS. Not having support for iOS is a dealbreaker. I want the same client.
3. No trial. As it seems like. I actually tried to download the app. There is a Sign-In page with a disabled Sign In button. I guess I need to subscribe to try it. I can spare $3, but I don't want to support subscription models. Seriously, give me an option to try it for 14–30 days, I will pay for it $100-$200, and you can ask me to pay you again for an upgrade in 3–4 years.
4. The main reason I don't want to try it, also because I am sure, there are probably some nice features, but at the same time, there are most likely so many issues with integrations between other apps. Like links from Reminders to the Mail client, or from Notes to the Mail client. And based on the roadmap [1] it seems like this is mostly MVP product.
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