Vet Golfer now 82 but still playing well off H/C 15( and a sometimes troubled shoulder). My Cobra AMP Cell Driver had had a slight upgrade shaft change when new to a Graphite Design YSQ 45 gram R Flex. Recently I tried a Wilson D100 Superlight with Graffaloy Prolaunch Blue in A Flex and felt more comfortable than the Cobra with GD shaft but 'lost' a bit of feel for where the clubhead was - maybe attributed to the lighter head in the Wilson. I am considering reshafting the Cobra with the Graffaloy A flex. Does anyone have any experience with this shaft in the Cobra adjustable head ? Would appreciate any relevent feedback. Thanks.