I haven't (so far) been able to find any specifications relating to the intermodulation performance of this design. Individual GALI-74+ devices have published values of +19.2 dBm typ. output power at 0.1 GHz and an IP3, +38 dBm at 0.1 GHz, so the LZ1AQ and Wellbrook designs are likely to be better in this respect.Note that the higher value of amplifier input impedance may result in this design being a better performer on the HF bands especially at frequencies >10MHz.