How to drive a linear MOSFET like IXTK22N100L?
Your circuit is commonly used as a current sink and therefore is fundamentally valid.The input C of your linear fet is high and it could form a nasty pole with the Opamps output impedence giving you control system hassles like instability or poor transient response .Putting in some gate resistance in would be wise because the opamp could be unstable into such a big capacitance anyway.An emmiter follower is good because it divides the effective capacitance seen by the Opamp by the gain of the transistors.I havenot  applied this circuit or its variants on a expensive linear fet .I would guess that your proposed linear fet would give better stability and transient response than the cheaper more common and less suitable switching type powermosfet.I have used opamps on smaller powerfets in a previous life .I did not have to do too much to the basic circuit to get it stable .