I wouldn't buy an eMax -- they are really basic budget tractors. I assume they are in the lineup only to capture a few cheapskate sales.
Money would be better spend on a Max if buying Mahindra. One of my few complaints about the Max is that the fit and finish is a bit sloppy compared to Deere/Kubota, the seat is terrible (you'll find better on a department store mower), and the loader controls are rough and lack finesse. Those are all areas the BX will be better at. However the Max offers better raw performance.
You really need to drive and get a feel for both of the machines to get an idea for yourself. Nothing beats a demo. Definitely pay attention to the seat and loader controls on the Max if you care about those things.