I believe it is common for graduates of top 50 schools, particularly from those that are ranked below 30 (for example, 38, 47 & etc) to secure placement at schools below the top 100 to 150.
Hence, the question to ask is whether below the top 50 schools, do you feel confident in securing a teaching position at all.
Definitely not. My boss graduated from a 120 comrehensively ranked university, but was recommened to a 60 comprehensively ranked university. So to have a good director (reputation in the field) could place you in a sound place. Of course, you have to work hard. And the top rank 50 will be meanlingness to you if you have realized it.