Galaxy Note 10 vs Galaxy S10+: Display Size & Notch
One of the most important parts of the phone and your decision is the screen, screen size, and the cutout for the front camera. Samsung doesn't do a notch like Apple, but the camera cutout on the Galaxy S10+ is as big as a notch.
Here are the hard numbers.
Basically, the Galaxy S10+ will likely fit perfectly between the two new Note 10 models. So you'll have your choice. Furthermore, Samsung's Galaxy Note 10 and Note 10+ will both have the same single-facing front-facing camera with a small hole cut in the screen. Much smaller than the cutout in the S10+, and centered for ease of use.
Some people love it, some hate it, and some don't mind the small interruption in the screen. You'll have to decide which size works for you and if you can deal with the hole.
You might also want to wait and try the Note 10+ in person at a retail store, as 6.8-inches with squared corners makes it a pretty big device. Oh, and don't forget that the smaller Note 10 only has a 1080p display.