I suggest that you send your scanner to Whistler for the Legacy Upgrade. It will convert your scanner to a Whistler WS1080 which will add P25 Phase 2 and DMR to your scanner. You will be able to use the WS1080 EZ Scan application for CPU firmware, DSP firmware, library, and application updates. There have been many reports of improved performance after the upgrade.
Second that above suggestion. Both my RS and GRE versions had noticeable improvement, and even do a very good job on the MPSCS simulcast system where I live.