It would be the same for all the current LimeSDR hardware that use the LMS7002M chip, the matching networks would provide some additional attenuation.
The people building Vector Network Analysers (VNA’s) using a LimeSDR used a minimum of 10dB of attenuation. I’d probably be a bit more conservative and use 20 dB of attenuation because I want to be standing well back from the cliff edge. For me the goal is to be sitting inside the safe zone and not teetering on the edge of disaster. You could always use something like a (JFW industries) rotary attenuator or a step attenuator and fine tune the attenuation.