I tried Amaxa for my iPSC (nucleofection was performed while the cells were in suspension) but it worked poorly for me, ~30% of the cells were transfected with control plasmid supplied with the nucleofection set but a few percent of cells were transfected with my plasmid of interest, so I switched to Lipofectamine STEM and it is working better for me. My colleague who works with primary neurons also tried Amaxa, both in suspension and as adherent cells (you need to have an extra adapter for adherent cells) and suspension also did not work for him, it was better on adherent state but at the end of the day he also swithced to LF STEM.