I had H&R Sport/Koni Yellows installed last Friday
and I'm very happy. I have an E-92 with ZSP, and the handling with the stock set up was skittish at best in corners (especially when the road is bumpy). Sometimes, the car would shimmy and float at the same time when I hit a series of bumps. That was not exactly a comfortable feeling. With the Konis, the car is now exceptionally connected to the road and the ride is slightly better than stock. I'm running with a full twist on the rears and 7/8 of a twist on the fronts. The steering is far more precise than stock, and body roll has diminished to a great degree. The car feels tighter and more competent. I don't track the car, so I really can't speak for people who are using a highly adjustable coilover set up at extremely high speeds. But on the street, at speeds up to 80 mph, my set up has been very effective and I highly recommend it.
I should note what my benchmark is. My last car was an E-46 M3. That car was an amazing handler -- precise, balanced, unflappable. My E-92 with the Konis feels better, except for the lack of an LSD (which is not something shocks and springs can overcome). But the ride with the Konis is much smoother than the M3's, which could become harsh very quickly on bumpy roads.
I should also point out that I considered getting sways, but decided to wait and see how the shocks and springs felt first. I'm glad I did, because I don't need sways with the Konis on the street (maybe I would if I tracked the car).
By the way, I'm guessing that the Dinan Stage 1 package is very much the same as what I have. Yes, I know that Dinan claims to have custom spring rates and perhaps even custom valving on the Koni shocks in its package. But I doubt that my set up is fundamentally any different and I saved more than $600....