Just upgraded to an Athlon 64x2 4600+ from one of those....felt it was a bit lacking performance-wise when multi-tasking/running Vista....
The 3200+ is a good CPU for average use/basic needs, so if that's all you're wanting to do the 3200+ 'll be fine. However, if you want to run Vista at its optimum and/or multi-task alot, you might want to consider something with a bit more grunt, perhaps a dual core, to save having to upgrade later on.
