The RR300 and RR500 are the brand new small turbines from Rolls Royce. The RR300 is going into the Robinson R66 and will soon be seen in a couple of fixed wings as well, so that's promising. We might se a lot more of those in the future.
I don't agree that the EA500 is overpriced when you compare it to TBM's and PC12's. It's half or even a third of the price (in the case of the PC12). Now, it's still too expensive to be an alternative for people stepping up from high performance singles - that I agree on. But compared to others in its segment, it's cheap.