I'm not sure about iMacs, but MacBooks have gone to soldered in RAM. That means you cannot upgrade it at a later date. Make sure you check that before you spec out your machine. I have a MacBook Pro with 16GB RAM and very rarely get into a situation where I wish I had more RAM. If you intend to do video editing or some serious photographic work you might want to think about 32GB.
Love the fact that the Apple products all seamlessly integrate together with very little effort. There are no issues with printers, external HDDs, or networked storage. I share NAS storage between DW's and my MacBooks and the two remaining Windows systems that we have with no problems. The MacOS user interface takes a bit of time to get used to, but seems to make more sense than the Windows 10 UI. Guess it's just a matter of preference which UI you like better. If you like using iOS on an iPhone or iPad, you will not have much effort to learn MacOS.