haven't confirmed the specs yet myself but Dinan advertises these mods to give 501 hp, 580 ft/lbs of torque (on all wheels) - it feels like a rocket taking off from a dead stop - (in Msport+ of course) even comparing it with my previous M cars. The suspension lowers the car 1/2" and gives it a noticeably more aggressive stance than the stock version. The free flow exhaust is a throaty base - lower tone than my M3.
I think the most noticeable change with these mods that I notice on daily driving is the performance suspension - it's a big time improvement on the stock 550i suspension - flat and tight around corners and no real sacrifice in comfort. If anything the comfort issues have to do with the stock all-weather run flats that came with the 550i. I'm keeping those until winters over.
When I bought the car, only the S2 chip was available for 2013 F-10's. Now the S3 is available and it will only cost about $200 to upgrade and that is advertised as bringing in another 10-20 hp - pretty close to the M5, only with all wheel drive. In the end, the only thing I miss with the M3 is the rev matching and DCT. I'm going to add an M grill to replace the chrome one - should look nice with carbon black.
2013 550i X-Drive M sport Carbon Black w/ Dinan S2,Suspension and Free Flow Exhaust
2008 M3 Space Gray - retired
2000 M5 Carbon Black - retired