I'm sure it will be reliable and quick - after all, they've been working on it for over a decade. Like PM, it'll be efficient at entering metadata, but it is so recent that your best bet is going to be to try it for yourself.
Yet why would one want to catalogue your images with a second program that doesn't show their adjusted appearance? While I think PM+ can read LR crops, you won't see other corrections made in LR like dust spots or WB, or where for example you lifted the shadows in a underexposed shot, made lens and persepctive corrections, made a shot B&W. When there are apps which combine adjustment and management, I don't see much space for one that only does the latter.