Your PCP becomes your personal physician, the doctor you see for routine medical care including annual physicals, immunizations and health concerns. POS plans normaly do not require any submission of claim forms while in-network. In a Traditional Plan you have complete freedom of provider choice. Services that have been deemed medically necessary are paid out on a variety of cost sharing co-pay and deductable options. They don't generally cover wellness and routine care, but it can be added in some cases for an additional premium.
Traditional plans are the most flexible plan however the are also the most costly.
They normally require submission of claim forms.