Going from Project Phono to DV P75 or Gram Slee

If I go from a Project Phono Box to a Dynavector P75 or Gram Slee ($500 to $900 range of phono stages), will I see that much improvement? I do notice that the Dynavector has 8db more in gain for MM cartridge. Wondering how much easier that will be on my amp. I do like the Dynavector cartridges (or similar) and plan to try a low ouput MC in a year or so.

System is Prologue II/Rega P5/Dynvector 20XH.
I have had extremely good results with the P-75/Shelter 501 combo.The P-75 will probably mate slightly better with a warm balanced cartridge or tube electronics,which slightly favor harmonics over leading edge transients.This combo situated on the Nottingham tt/arm has a real synergy to it.
The extra gain of the phono stage will not make things "easier on the amp". The higher signal level will force you to lower the volume control, which, if you believe that pots are bad, is not helpful. Ideally you would lower the circuit gain so that the volume control was at maximum. But all this is theory. If the new preamp stage sounds better it won't be because of gain.
My analog system sounds really nice as is - just wondering what a higher grade preamp will do. I suppose I'll wait and just keep buying more vinyl.
Tpsonic, have you had a lower grade preamp than the P75 and if so, what was the improvement?
The Era Gold Mark V embarrasses the Dynavector.
I started out with a Creek OBH-15, which i thought sounded really good, then based on many, many recommendations upgraded to the P-75, the difference that i noticed immediately, were a more quiet background, and higher resolution, everything sounded alot clearer, overall i'm happy with the Dynavector (especially if you use dyna carts. it's a no brainer)
Well, I guess what I am saying is that, being a vinyl newbie, it's hard for me to imagine a big improvement because I've discovered how good vinyl can sound. (I went from a Radioshack table to my current table)
Plinko,I have used Klyne,Vendetta,EAR,Krell and Walker Signature&Reference phono stages.