I installed a Z3 rack on my car. I can't really compare it to any other racks aside from stock but I highly recommend it.
Z3 rack is 2.7 turns lock to lock.
I don't know if I would call it twitchy but it is very responsive. I also deleted my power steering so it probably feels a little different then a Z3 rack with power steering.
I think it cost me about $600 for the swap. That includes a new rack, new tie rods, E36 rack swap kit, and power steering delete.
You can read about it here...
Oh and read this...