Mark,I've done lots of testing to see what happens in various temperatures with ultra slow sink/float and 'neutral ' density gliders. I don't have the results to hand but can probably find them if interested, thing is , as bob kinda alluded to- the difference in lead ballast between each stage, i.e float,suspend and sink is tiny . I tank tested using 3 temperatures of water ,lets say very cold,medium and tepid . I also chilled and heated the lure ,very cold, medium and warmish . The lure reacted differently with each combination, this showed me that if you manage to achieve neutral suspended density it will only do so under the exact temperature conditions when it was tested. The chances of encountering the precise temperature of lure and water again are practically zero. At one point I managed to truly suspend a big glider midwater which was pretty weird looking , almost certain the water had temperature layered and lure sunk in top layer till it suspended /floated on bottom layer. When I mixed the water it sunk . In practice a lure ballasted to sink ultra slowly in a test tank can float when fishing ,which for a slow sinking glider is no good , hence the exact figures from my tests are meaningless - a sinking lure has to sink regardless of conditions ! Dale I get what saying about preferring a crank to rise but for many species a lure that stops abruptly and near suspends in a fishes face can be very effective. ..