I am a big fan of hard sci-fi, and he does an excellent job of it without letting it cramp the story or limit the scope of human space colonization (those limits help make the story rather than constrain it). Plus, he has a whole series that's basically space pirates (Revenger) so hard to go wrong with that haha.

Most of the stories are set 100 to 300 years after Star Trek takes place, but FTL travel is non-existent here. Things like inertial dampeners that are basically handwave plot devices in Trek are a huge deal in his stories (i.e. very experimental, of alien origin, and absolutely horrifying when they malfunction or are pushed beyond their "safe" limits).

Reynolds used to work for the European Space Agency, and he absolutely brings that to his stories and shows his work. One of the big (pun intended) areas he excels at is keeping the scale correct when parts of the story take place in-transit between various star systems.

Some critics complain he doesn't end his stories very well, but I've only had issues with a couple (mostly because it seems like they were set up for a sequel that never came about).