PA Association of Realtors Form Lease. Benefit to use?

[Kevin M.]

I notice a lot of property managers in my area (Philadelphia) use the standard form lease approved by the PA Association of Realtors (PAR). My company uses a personalized lease with many additional terms that address specific issues not covered in the PAR form. Admittedly, our lease is more landlord friendly than the PAR form. It has been reviewed by an attorney. 

Other than the simplicity bonus of using the out-of-the-box lease provided by PAR, is there any other reason not to use your own? Does anyone in Pennsylvania have experience with eviction courts ruling more harshly against customized leases? Any discussion or feedback is appreciated.