For a more indepth analysis between R32 and R410 can refer here
https://www.sciencedirect.com/science/artic...140700712003532R32 does have its eco friendly benefit in terms of ozone depletion, but for very hot ambient (46C) it start to struggle. Minus 18C not achievable unless you're doing cold chain logistics. Between these two extremes at normal malaysian ambient ~30-35C no significant diff between R32 or R410 cooling performance.
In terms of model wise as long as it has an inverter, even R410 also will work well, coz it can run in slow mode when it has reached target temp and continue to dehumidify the room - whilst non inverter will stop the compressor and run fan only mode in the IDU - it starts to get stuffy*. Do note, Inverter will begin to save power only after the room has reached target temp ya.
*and this is why some ppl who were used to the non inverter models always put it freezing cold at 16C to force the non inverter AC to run nonstop
*this behaviour of setting extreme freezer temp at 16C to force AC to continue running all the time is not required as inverter ACs still continue to run slowly even after it has achieved target temp of say 25C, as it didn't fully stop, it will continue to dehumidify the room

The 24K btu Pana looks like a better bet in terms of btu to $; as it will be able to cool down the room faster than the other 20K btu models shortlisted.
In terms of big AC longetivity..R410 compressors may actually last a bit longer than R32 compressors as the R32 ones run hotter than the R410s.