I've just had mine for a couple of weeks and let me say that this is a dynamite machine. It's quiet, very fast compared to what I was using, and it runs everything including my old drives. I've heard that Apple is planning to continue supplying these workhorses as long as the demand continues.
I got mine through the Apple store at the educational discount. I took out all the extras including the nVidia card and got the final price down to just a hair over $2000.
Good for you the 1.25 has some nice features over the G5 - extra drive bays being the main one.
There is so little margin in new boxes that getting it locally on a plain jane box is smart, specially if you got a deal
If you really want speed we have some tips