I had Stage 3 and Shockwave done on my 550i about 3 weeks ago and combined with my H&R Spring replacement [my 1st mod done] and it totally made the car what I think BMW should have offered when they made this car. I mean when spec'd with the M Sports package or Sport package I think a Performance HP/ECU upgrade along with Performance Exhaust and suspension package such as what one can cobble together with Dinan should have been available. But I digress...to me I think the Shockwave plus the Stage 3 just ties down the car more and gets rid of alot of the suspension travel and body mvmt which you sometimes feel on the base car when pushed aggressively or sportively driven. It corners more flat and rotates better in corners and with elevation changes IMHO and with speed...something the base car does not like...push a base 5 series without mods and you definitely are VERY quickly reminded of its size/heft. With the Dinan Stage 1-4 and Shockwave or aftermarket springs...not so much. There is a limit out there but its stepped out/moved quite a bit man. Just my 2 cents...
'14 F06 650xi GCoupe wDinan (Carbon Black)- Mine
'10 E70 X5M (Sapphire Black Mettalic) - Mine #2
'12 F10 550i (Dinan modded) - Gone
'10 E71 X6 35iDrive SAV (Space Gray) - Gone
'08 e92 M3 coupe (Sparkling Graphite) -Gone