Cartridge for RB300 other things

I have a Rega P-25 with the RB-600 arm and a Grado Platinum.I find the Grado to put the arm at the best VTA with no spacer.It gives it a slightly negative angle.I used 1 spacer for several weeks then removed it and the midrange smoothed out,the bass deepened and it just sounded better.The grado hum is no issue with me.I have never heard it during music or even between tracks.Only when I raise the arm near or at the end of the LP.

thanks to everyone for thier fast and informative feedback. about the grado, what does a replacement stylus go for? also would still like to get some imput on the mats and any other tweaks. thanks a million

You cant put a new stylus in a Grado.When you need a new one you trade the cartridge in for a new one plus it costs 2/3 of what the cartridge lists for.I never had any luck with Ring Mats.I had one but returned it as I heard no improvement.Quite a few tweeks for the Grado arms but I need to sleep and will post them another time unless someone beats me to it.zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz

zzzzzz sorry,Rega arms zzzzzzzzzzzzzz

Dynavector 10x40 II works fine for me on my Planar 3 with OL-modified RB250 arm. Needed a spacer to give a neutral VTA, but like David with his Grado, I prefer no spacer and a slight negative VTA. I see that the Ring-Mat people now offer a package, as expensive as it is ingenious, that includes platter-sized shims for convenient and precise VTA adjustment; the shims are supposed to reduce resonance, also. Good to have cautionary feedback on Ring-Mat from David; you'll find mixed reviews on AudioReview, also. At the risk of giving advice that wasn't asked for, I'd not monkey with mat changes until the major issue of cartridge change is settled and you're thoroughly familiar with the new sound. You asked about other tweaks: More than a tweak, I guess, but I will spend my next Planar 3 dollars on a DC motor upgrade.