Seems high. I nearly purchased a 2013 M-line 335ix nicely optioned and with 7500 down, monthly would have around 690. Not really that much more and it was to own, with none of the restrictions of leasing (that was 57k, but deal was on 55k) dealers don't like to negotiate 335s.
Current: 2010 E90 M3 - JBM PP,TP,ES,CW,Beast
Retired: 2012 F30 335i Sedan - Sport Line