I never read any “fake” Asimov stories not actually being written by Asimov himself.
I have however read everything Asimov wrote, I think he was an amazing author, and I love how well thought out his stories are.

Is there any particular reason to read these Roger MacBride Allen stories?
I must admit my interest in reading has diminished, because I find mostly everything I read has become banal and without any new thoughts.