Robin, if it works allright for you it IS ok of course but at the same time you probably have not tried some better alternative either so you can not know what you possibly are missing. What is "wrong" with the anglo handle is this:
1. The handbar location makes the contact unstable. The instrument wants to wobble so that you use fingers or the wrist to stabilize it. There are german style "anglos" having the handbar at the geometrical centre ( which at the best also is the centre of gravity
2. The hand slips within the handbar so you either let the instrument rotate ( clockwise looking at the right side) or grip it with the thumb to keep it in place (of course when resting the instrument on the knee this is partly compensated
3.The bar/handrest usually has even height but ought to be slanting so that it is lower at the thumb and higher at the little finger side ( to make the fingers hit the keys in line with their travelling axis )
4. The handstrap locks the midpart of the hand and thus restricts movements by the fingers. With a wrist support combined with a wrist strap a stable connection may be achieved while fingers may move more freely
5 Combining the wrist strap with a thumbstrap offers the best stability
6. The handbar locks the hand making it difficult reaching the distant buttons on the top row. The handbar/wrist support should be closer to the keyboard at the little finger side ( unless you have very long fingers
7. ( apart from the handle issue, the air valve better not be controlled by a press button but a lever working sideways instead)