ok, it's good that the lifter position did'nt change.

The test you performed proved that the valves are sealing aginst the seat when the valve is closed , which is a good thing, it means there is no leak down when the valve is closed.

What it did'nt test is the integrity of the valve guide and its seal.

as you know when the engine is shut off oil reacts to gravity and seeks its lowest point, as oil drips down it can run down the exposed portion of the valve stem past the seal and into the cylinder depending on if the valve is open when the engine is off which can cause start up smoking.

I dont know the mileage on your X but if it was at or around 100k I'd have the heads at the machine shop getting the full treatment.If your going to go through that much work it only makes sence to have the cylinder heads professionally checked.

I hope it all works out for you.