A KSOP is an alternative to a company sponsoring both an ESOP and a separate 401(k) plan. Whether you adopt a KSOP to begin with, merge an existing ESOP and an existing 401(k) plan, or simply amend an ESOP to add a 401(k) feature, maintaining one plan will definitely be less expensive than maintaining two.
The cost savings on maintaining one document and filing one Form 5500 will be enough to justify a KSOP, but the most significant savings are achieved if your two plans are large enough that they are subject to an independent audit. By merging the two plans, you go from paying for two audits to paying for only one. This will save you thousands of dollars.
There are very valid reasons for adopting a KSOP. Contact RWG for more information.