Lol pulling ur pissers sorry..
G all the way. The springs are used for boost transition / reaction between manifold pressure and vacuume. Stronger the spring with higher boost the sharper the movements. The electromagnet side of the DV body only "opens" up the piston it cannot add force to clamp the piston shut... Sounds strange?? The DVs use the basic physics of equal pressure on both sides of the pistion, in the centre of the pistons D and the G the is a hole which the boost pressure flows into resulting in the pistion being pushed hard closed shut to hold the boost back. The G is fully air tight from day one and has a nice rubber ring to seal on to the alloy surface. The D uses a plastic sealing on the piston body this is not an air tight seal even when brand new that seal leaks in most cases, if not then afters a few weeks the plastic ring becomes slack and leaks.
Treat the G DVs as a consumable item change every year and the rubber quality will degrade over time with the constant expansion, pressure heat, movement and oil.. For £35-40 it's worth doing every service along with the hpfp cam follower
Hope this make sense, lol Sunday pm trying to watch superman 3, kids running a riot around the house and trying to type on a iPhone with dog laying on my arm...