That all depends on yourself. If you already have the skills necessary to complete the MCSD-VS6, then by all means do so.
However, if you're starting from scratch, IMO, you'd be better off pursing MCSD-.NET. However, IIRC, the ETA on the Architecture exam for MCSD-.NET isn't until early 2003. Until then, you'll be in hurry-up and wait mode. Thus, I'd suggest you first do the MCAD as a stepping stone to the MCSD. Jon Hawkins