Hello Donn,
If I choose "replace all" it's not clear to me whether identical files are going to be uploaded all over again, or not.
The "Replace all" button means that out of all files that you want to transfer, all matching ones will be replaced - please note that it also applies if the name and extension of the files matches, i.e. Remote Utilities, unfortunately, does not have a feature to recognize the files with the different "Modified" date and mark them as different files yet.
If you select "Replace" instead of "Replace all", then it will only be applied for the current file - for example, on your screenshot, it's the file with the name "Local-223-Code.mdb". After this file is replaced, you will be prompted to the same dialog for the next matching file.
This means if you transfer 10 files to your remote machine that already contains the same 10 files, and 5 of them have a different date, but the same name/file extension - the old file at the remote computer will be simply replaced. The rest of the 5 files (that are completely identical to the ones at the remote machine) will be transferred once again and replaced as well. To summarize, you will still transfer all 10 files to the remote machine.
Hope that helps.