The Z4 23i / 30i automatic came with the 6 speed ZF 6HP19 box. The 7 speed dual clutch was only available on the Z4 35i / 35is. Mine is an automatic, which is what I wanted, and I’ve no complaints at all. It might not be as slick as the 8 speed on our XF but there isn’t a great deal of difference. Changes are sharpish and if you push the stick over to the left you get sport mode which is great for driving on a twisty road. I wouldn’t change it for a manual but no doubt others would! 
I’ve no experience of split rims but every time I see any they seem to suffer from corrosion around the bolts but wheels are very much a personal choice. My car came with CSL replica wheels but the rears where the wrong width. In the end I changed them from 18inch to 19inch Riva DTMs as I liked the style.
I’ve no experience of split rims but every time I see any they seem to suffer from corrosion around the bolts but wheels are very much a personal choice. My car came with CSL replica wheels but the rears where the wrong width. In the end I changed them from 18inch to 19inch Riva DTMs as I liked the style.