They look great and much, much better than the before shots that is for certain !
Even as a professional woodworker, I elected to have my floors professionally refinished last year. Two man team with heavy drum sander and edge sander. They did a great job and applied three coats. Two left the grain a little "hungry". Like anything else it is the details that make the difference . . . specifically the time spent sanding between coats and wiping/vacuuming the dust before applying the next coat.
I had originally planned to do it myself with the orbital rental unit, but my oak floor was stained cherry and I wanted the cherry color gone. Cherry stain on oak is just wrong. I was told that to sand the stain away the big dog drum sander with a pro operator would be the ticket. Now that the stain is gone, if it needs refinished down the road I'll probably do it with an orbital sander.