Welcome! e_magnum.
F14s are actually one of the favorites among here and good bang for the buck! They are so popular now that some of the shops in Hong Kong started ordering them from the US on a routine basis. There is an Advanshop that I got mine and they have a shop in HMT on the kowloon side as well.
Sold mine because the F14s are everywhere in HK now as they also fit the C63 and others. Too common..... I will also be selling my set of Forged1 in about 2 weeks but you make your own choice
I also have ACS on (mine has DHP as well) and I don't think they are too low at all. My previous Eibachs are definitely lower (and softer) than ACS and that presents more of a problem. You have to factor in what kind of road you drive to decide on whether lowering the F10 is suitable for you. In terms of comfort, ACS is definitely firmer, but doesn't compromise too much. In fact, it takes much of the boat ride feeling off from the F10.
Going to 20" wheels with non-rfts will probably net you the same in terms of ride comfort, with the benefit of better cornering. But then it also depends on the tyre that you choose to go with the 20". A warning, though. Current breed of 20" tires that fit the F10 are mostly sport tyres. And they are definitely a bit noisy compared to your stock tyres......
I think F14s for the F10 in 20" are around HKD22k-24k. ACS are pretty much HKD4-5K for springs, excluding installation and alignments.
I think most of us are getting the 3D design stuff from Zillion Performance, which is also across the street from BMW Matauwei service center. They are on facebook.
Hope this helps a bit. I don't know much and am just filling in some preliminary information for you. Gurus RC3, Grimmy, and quite a few others are more into mods and they will probably spill their guts later on when they are free. From their day jobs, of course
