I now own both the Lekato WS-50 (5.8GHz) and Nux C-5RC (5.8GHz). The Lekato was bought as a 5.8GHz upgrade to my Line 6 2.4GHz unit (which was good but suffering 'occasional' drop out, probably due to the bands I was in moving to digital mixers) and I was very happy and have zero complaints. I've recently however, joined a new band (and resurrected an old band), so felt that the NUX's ability to recharge on the fly if needed, was useful; added to which the NUX seemed a better quality unit (inc the on/off switch).
A/B there is nothing in it between the units... literally nothing. I tried them with passive basses, actives (inc 18v), piezo loaded bridges and a bug on a Double Bass; no difference between either unit. I will say that there is a tiny bit of difference (through quality headphones) between the 2 units and a regular 1/4" lead BUT that could simply be that the lead had no boost which the electronic devices must have been giving (they were slightly louder cleaner/toppier). If I could put them on a scope maybe I'd find detail but in everyday use 'nadda'! The NUX certainly feels more premium but on a budget, the Lekato would suit many. However, I appreciate in some situations, certain basses/equipment appear to not work as well with some units but I couldn't replicate any issues that others had.
£50 v £150 (approx) you pays your money...