It depends upon the resort as to the exact configuration. At OKW, the studio will have 2 real queen beds. At all other resorts there will be a queen bed and a full-sized sofa sleeper.
There are some advantages to the lock-off units, depending upon the make up of your party. The folks in the studio portion will have a little more privacy and independance, as they will have an exterior door and can come and go without disturbing the people in the one bedroom section. They can also make their own coffee and snacks in the the kitchenette without disturbing the one bedroom residents. However, they will have less closet space than they would in a true two-bedroom unit.
The basic room configurations, other than the exceptios mentined, will be similar to a dedicated (non-lock-off) unit