XL is a fine oil for 7500 changes. The public may be more receptive to the OE as it is cheaper, and geared for OLM/6000 OCI's that are becoming the norm. TBN is a little weak for my taste, but may try it for my daughter's vehicle. Both are API SN certified and meet Dexos 1 specs.
Amsoil is working to gain Quick Lube or "Do It For Me" markets. The OE should be on par cost wise as Pennzoil Platinum or QSUD in the quick lube market.