budget phono preamp selection

After reading countless threads here and elsewhere, I seem to have narrowed down my "budget"($250) phono pre's to the Cambridge 640 or the Musical Fidelity V-LPS. I currently have the Nad PP3 but am not satisfied with the overall sound(not too dynamic, kinda "1 dimensional"). I want to convert my LPs to CDs over the winter, so thought the Nad w/usb would fit the bill but can't say I'm all that impressed with it.I've got an M-Audio sound card I can use instead of the USB. First, will either of these two make a substantial difference in sound for me over the Nad? (Music first). I have a Music Hall MMF5.1 TT,(Goldring1012GX MM) Sunfire TGII(w/phono stage)reciever,Sunfire Cinema Grand Sig.Amp, Definitive Tech speakers. Am I looking at this clearly? Ideally I would like a phono pre that would have a very good sound on my system and then be able to use to convert my LPs to digital later without having to spend too much.Thanks in advance for any input
At your budget,I don't think you will see a lot of improvement.Just a thought.Good luck in your search.
I'm thinking you should be able to get decent sound out of your MMF5.1. Have you checked your tracking force lately/accurately? I'm guessing you are tracking too heavy or else are too "low" in the back of your cartridge and need to raise the back of your tonearm or remove any record mats. Fact is, most of us don't have our turntables set up optimally. Play around with it and listen to the differences.
Adjust accordingly. (Really cheap tweek, zero.)
Take a look at the Graham Slee. I think they have one for about $300.