You can still use the scanner for snapshots, meaning you'll have digital files.
The enlargers give you quality the Plustek could never match if you want a great print from the same 35mm negs.
The only thing you'll lose is immediate feedback while shooting, and what's that worth to you?
To me the important bit is that you have complete enlargers that aren't missing any important pieces, like neg carriers, etc, which can be both a pain in the neck AND expensive to track down.
Money wise, it's hard to tell whether you're coming out ahead, so it becomes a comparison in utility. It seems to me you'll have more fun with the darkroom, if I am understanding you correctly, and that alone should be a big box checked in the 'pro' column.