You don't need a perfect mesh to do RE; you just need enough of it to reconstruct important features. So, for instance, if you had a cylindrical boss on your original part, all you'd need was three good points on the mesh to recreate the circle, and one on top to show you where to end the extrusion. The mesh is just for reference, and once you've created the CAD model you can dump it - the CAD model is your final product.

3DCoat is intended for modeling organic objects, texturing them with UV maps, and remeshing them to clean up your models, but I don't think it makes any claims for being a reverse-engineering tool, or something that will perform mesh repair on scans.

Andrew Werby
www.computersculpture.com