Hi your post really got me thinking. I have been considering asking my NS to consider giving me a programmable shunt with my next revision. Now I am considering the MIETHKE proGAV. I do not even know if it is available in the US yet, but I really like what I have read about it. Until recently I thought that I didn't have a choice and that my NS made the decision. I have had my shunt for more than 40 years and still have so much to learn. Thank you!