Preamp/amp far superior to just int. amp.?


I am curious if there is that much of a jump up in sound quality if a person goes from an integrated amplifier setup to a preamp/amp setup within the same manufacturer? I realize this is a loaded question, and it is somewhat rhetorical, but I just wanted some feedback if I threw it out there.

The reason I am asking is because I am wondering what my next upgrade will be in the future (not near future), because I have an excellent budget amp (Rega Brio 3), but there will come a time when I go to a better integrated amp., or spend the same amount that I would spend on that int. amp. and perhaps buy a not as good brand's preamp/amp. What would give more bang for the buck for say, $2000? I guess that is my true question.
regafan_1972
Rich:

Excellent response to my question. I really appreciate your insight and I will definitely take it to heart and keep my integrated for now until I can eventually audition some tube equipment. Until then, I will buy a DAC for my Squeezebox and/or a used, quality CD player until I can afford upgrades.

Thanks again.
For 2K I would second the integrated route though there are lots of paths to salvation....good luck,Bob
I took everyone's advice and upgraded to a Rega Mira 3. No seperates for now, just the Rega quality integrated.
For your $2k, I would have recommended a used Simaudio I-5 or I-5.3 integrated amp.