Jim also has an Invacare and loves it. He has the TDX SP with elevated seat and tilt/recline option. We were able to program the chair to do what we wanted. Shhhhhh, our orthotic guy gave me a programmer. So, ask them to program it to your specs. The lock out can be turned off or on and usually comes on from the factory. Jim also has an air cushion called a ROHO and elevating leg rests rather than a foot board.