Many people regard the RB300 as being a very solid foundation, though with some room for improvements due to compromises made to reach its price point. You see mods for these arms more than for any others. Some of these are DIY kits for just rewiring. Origin Live also has more comprehensive mods, IIRC. Currently one of the more highly regarded modded Regas is the Audiomods arm. Had an RB300 and the improvement when I moved to the Audiomods was significant. And I experienced a significant improvement when I moved up to a Moerch DP-6 and then DP-8.
But yes, Petermax does make a good point that it is important to gauge what improvement will get you the most bang for your buck.
But yes, Petermax does make a good point that it is important to gauge what improvement will get you the most bang for your buck.