I use Premiere with Cineform AspectHD and like the work flow. We mostly shoot DVCPRO50 but it works flawlessly. I mean I would love direct import but unfortunatly who knows if that will ever happen with Premiere. I am excited for Matrox's 2.5 utilites update coming out soon because we also have a LE system here. The new update will have direct mxf import. But if your wondering if Aspect is worth the money I would definatly say yes!
I'm about to get Aspect HD as well. Real time effects, improved performance and a visually lossless codec are a good trade for the conversion time. Great people working at CineForm too; David here on dvxuser, and also Tim who replied very promptly to an email I had with some very specific questions.