Well if you are using very sophisticated modelling programs, they will be influenced more by the graphics card than the processor. Besides this, HyperThreading in most cases causes lower performance in 3D modelling situations compared to an equally clocked Pentium 4 without HyperThreading as is demonstrated in Tom's benchmarks http://www.tomshardware.com/cpu/20021114/p4_306ht-20.html.
Furthermore, the Pentium 4 (especially mobile models) is reaching the end of its life, whereas a Banias-based notebook has a much higher probability of being upgraded. And lets not forget that the Voodoo most likely does not have an upgradable graphics card.
If you were to directly compare a Pentium-M 1.7GHz to a Pentium 4, you would find that it performs somewhere, just under the 2.8GHz range, not only this, but at this speed, it runs cooler and requires less power all-the-while giving you high performance. From my point of view, why get a notebook if it is so hot and heavy that it becomes a burden to take it from place to place?
Also, in the past when I have compared Alienware/Sager/Eurocom/Clevo notebooks to other notebooks (namely Dell and Compaq), I have found that the performance of the almost identically spec'd computers is more often than not lower with the Alienware/Sager/Eurocom/Clevo than with the other notebook. For instance, my old Inpiron 8200 (P4-m 1.7GHz, ATI Mobility Radeon 9000) scored the same 3DMarks as a 2.4GHz Alienware with the same graphics card.
In addition to this, 3D Modelling can often utilize the Hard Disk quite extensively and as far as I know, the Voodoo m600 doesn't ship with a 7200rpm 80GB HDD. I believe the Voodoo m600 system also has a maximum memory amount of 1GB, compared to a Pentium-M's 2GB maximum memory -surely if you want the best performance regardless of cost, you would want as much RAM as possible, especially if you need your notebook for 3D Modelling.
Don't take this post personally, I am just presenting you with alternative ideas, so that you know that when you purchase your notebook, it is the right notebook for you and it covers all your needs.
RaPTuRe
Who's General Failure and why's he reading my disk?