Preamp design approach - Power Supply location

Looking to hear from some design types or those who know something on this area. I have had both type of preamps and cannot myself say which is better but am very curious as to the perceived advantages of using external vs. internal power supplies (or vice versa).
I think that Herman is correct, if you consider shielding as part of the power supply. Most design decisions involve compromise; I expect that is true on this issue as well. Certainly more cost to go to a 2 box solution. Those $ could be used to provide a bigger, better filtered and shielded supply in a one box unit. There are excellent examples of each, for sure.

I have experience in my system with both internal (cj 16LS, ARC Ref 2, Hovland HP-100, Lamm LL2) and external power supply pre-amps (A.I. Modulus 3A, Cary SLP-98P, and First Sound 4.0 w Paramount Plus upgrade).

While it is difficult to say what each pre-amp would sound like with the opposite power supply approach (don't have access to their prototypes--if they ever existed), I come down on the side of external P.S's.

I don't care for the extra chassis and connecting cord, etc. hanging around, but I am more willing to accommodate them than not.