I've been using a Kenwood TS-2000 for HF the last 15 years and just picked up one of the Flex-5000A models, with ATU and Dual RX. I am simply blown away about the sound quality and the receive on this rig. I have never been able to hear so many stations (and SEE them). With a little tweaking of the settings, you can reach near FM quality sound, if not better. I haven't had the rig long, so I'm no expert, but I am very happy with the purchase.
In my opinion the Flex-5000 with the continuing support of KE9NS is about the pinnacle of SDR for 80 to 90 percent of ham radio operators. With ATU and 2nd receiver plus the UHF/VHF modules it will do it all. There are so many options and use modes that I never get bored using this rig.
Operating perimeters are infinite. Follow https://www.youtube.com/watch?v=fV_iolSf3OA W1AEX's excellent video on setting up the audio train for each mode and this baby rocks.
After using it for 3 years i only can say "Best rig i ever owned"
Nothing to complain about, and with the latest updates from KE9NS it can beat any transceiver
Most flexible and easiest operating rig I have ever had. Also have the ATU, second receiver and VHF/UHF unit.