Yeah Eibachs offer a good drop 35 - 60mm I think and those ones advertised are applicable to our 335D's. Only thing is that where BC coilovers (what I'm getting) which are about £700 max Brand New come with everything you need (including camber plates), you'll have to go out and buy your own ones if you get the Eibachs etc. KW however lie in the same boat with BCs in which they come with ready made good to go camber plates...someone correct me if i'm wrong tho... KWs however are more expensive although they generally are the preferred choice for many people who can afford top dosh.. from KW v1s from £800 to KW V2s £1100 or so etc..V3s would be a straight overkill unless u go heavy track days..
If you're in no rush and can wait... do some more research. I guess I made a hasty decision to buy those BC coils but luckily did a lot of research beforhand... if they weren't at that price, I probably would have held off buying until next year but couldn't resist LOL.
Stick to BC, Eibach, KW, Bilstein etc etc. Other brands may attract you price wise, but may not perform as well but again, all down to the end user :-)
Now: E92 335D
Gone But Not Forgotten: E90 320D Alpine White