The Aeron is better than Embody from HM, and by far the best chair I've ever used, so go for it! Markus is way better with textile cover rather than the leather one due to breathability.
Regarding your monitor setup, I'd advise you to use a vertical stack compared to the horizontal one or a single monitor. The keyboard and monitor(s) should be aligned vertically so you don't end with your hands typing in one direction and looking in another direction.
Otherwise, with time, you risk injuring your spine/neck.