I have a LimeSDR and although multiple channels is nice, the device/software is a bit buggy and I wish I'd gotten a HackRF instead.

BladeRF is pretty cool. It doesn't have quite the frequency range of HackRF, but it's full duplex, and uses 12-bit ADC/DAC (vs. HackRF's 8-bit ones). Also it uses USB 3 so the bandwidth is not limited to 20MHz. (I think it's around 40MHz.)

Analog Devices has done the ADALM-PLUTO which is less expensive than the HackRF-One. I don't have one of those but I do have the HackRF one, and if UPS is to be believed a LimeSDR :-). The cost/capability matrix is sort of

RTL Dongles -> ADALM -> HackRF-1 -> LimeSDR -> Ettus SRP

The RTL's don't transmit but all of the other ones can.