I'm surprised with the results so far (57%/43% in favor of P&R). I love both of these shows and have binged them start to finish a few times. For me however, the Office is a huge step up because of a few factors:
1. Combined the comedy and drama perfectly (Jim+Pam is legendary). Parks never really got this right IMO, I never felt really invested in the relationships of Andy/April, Anne/Chris, Leslie/Ben, definitely not to the same degree
2. The casting of the backup casting was better in the office, IMP. Stanley, Phyllis, Toby, Creed, Meredith were all great characters, whereas in Parks/Rec I wanted the show to stay focused around Ben/Leslie/April/Ron/Andy at all times. Gerry and Donna episodes put me to sleep.
3. The Office always seemed like a few crazy characters (Micheal + Dwight) in a normal world (Scranton seems like it could be a normal place) and Parks and Rec was more a few normal characters (Anne Perkins + Ben Wyatt) in a crazy world (Pawnee is a strange, goofy place). That appealed to me way more.
That said, both great shows. Throw in Community and you have my favourite 3 shows to binge watch over the last 10 years.