Converting from Window to Mac

Yes. There are many differences, some large, some small. Whether they are of any consequence to you or not depends entirely on what features you use in Quicken. There are also some things which don't convert, but the features exist in Quicken Mac. For instance, attachments don't come across, but you can do attachments in Quicken Mac; budgets and reports don't transfer, but there are budgets and report sin Quicken Mac.

There are dozens, if not hundreds, of posts about transitioning from Quicken Windows to Quicken Mac on this forum.  A few are here, here and here. But as several people wrote in those threads, the best thing to do is try out Quicken Mac if you have access to a Mac; your existing subscription allows you to download and use both Quicken Mac and Quicken Windows. Because we all use Quicken so differently, what I might tell you might not be important to you, and I might not think to tell you something which is very important to you. 

If you don't have a Mac on which you can try it out, you might want to ask some specific questions here about things you're concerned about in potentially switching from Quicken Windows to Mac.

I'm a longtime Mac user, so I can't answer from the perspective of a Windows user, but I'll chime in. I do think the stability of Quicken Mac is one of is often unheralded strengths. I used to use the legacy Quicken Mac app (Quicken 2007 at the end of its life), and one of my concerns with it as my data file grew and the software aged was that it crashed not infrequently. Most times, it was a simple matter to relaunch and ru a maintenance routine to rebuild the database indexes, but on more than on occasion, I suffered some data loss/corruption. Since moving to Quicken Mac, and its modern SQL database, those concerns are gone. That's not to say something can't go wrong; something can go wrong with any software or hardware. But I find Quicken Mac is rock-solid reliable. (There isn't even a database repair utility, as there was in the old Quicken Mac and in Quicken Windows, because it's not needed.)

The current Quicken Mac started development back more than a decade ago and came to market as Quicken Essentials in 2010. It lacked many key features Quicken users were accustomed to, but it had a solid foundation. When the current Mac development tam began work around 2013, they had to rip out and replace some significant parts of the Quicken Essentials code to modernize it yet again to work with the latest changes to the Mac operating system. When Quicken Mac came to market as Quicken 2015, it still laced a lot of functionality, but it had a modern code base which could grow with the Mac operating system. When Apple started the switch away from Intel to its M1 hardware last year, Quicken Mac was easily updated to run natively on the M1 Macs from the day they came to market. 

There are still many features, large and small, which Quicken users are waiting/hoping to see added to Quicken Mac. Development of new features is slow, but if you compare the current Quicken Mac to the program 2 or 4 or 6 years ago, you'd see that it has improved by leaps and bounds. I haven't seen anything to lead me to think this won't continue. The developers know where most of the pain points are, where Quicken Mac is missing capabilities compared to Quicken Windows or the legacy Quicken Mac; I feel they're continuing to make solid progress, although it's slow going to add literally hundreds of things users have asked for. 

So in terms of the foundation, stability and future of the platform, I don't think you can go wrong with Quicken Mac. The question is whether there are any features you use in Quicken Windows which don't exist in Quicken Mac which would be a big enough obstacle to block you from switching. That's ultimately something only you can determine; we all use Quicken differently, and what might seem like a minor issue or non-issue to me might be a big one for you, and vice versa. The best way to figure this out is to try converting your data on a Mac and working with it for a bit. That's tricky if you don't have a Mac and your purchase of one depends on whether you can use Quicken Mac successfully; it's something of a Catch-22.  Do you know anyone who has a spare/old Mac you could borrow for a few weeks to try it? Or can you find a retailer of Macs who will let you return it within a month if you're not satisfied? Or who does short-term computer rentals?