We looked at CADWORX and found it an ok package but only basic functionality with limited speed improvement. We also tried Plant4d and autoplant. The autoplant we will not touch again and they have are no longer on the autocad developer network so there future is in doubt. The Plant 4D was what we settled on. Not much more investment than Cadworx but much faster drafting and a far more intelligent system and it sits on Autocad or microstation. You can get info on the plant 4D from