We are almost finished with EM book A and I still love it so much more than Earlybird. We are doing almost every page in the book, whereas with Earlybird we were skipping many, many pages.
I will say that EM book A seems a little bit more basic than Rightstart level A. With Rightstart we have worked (and finally have down cold!) recognizing the quantities 1-10 on the abacus without having to count. Rightstart then goes on to pursue the idea of even/odd and writing the numerals.
In EM we have covered: same, different, sets, counting to 10, number order, shapes, patterns, length, size, and weight. The last units are on capacity, equal sets, more, and less.
So, I have decided to finish out EM before moving further with Rightstart. We have just about finished MEP Reception (which seems to be the easiest of the 4 programs for my dd) and we still play around with Miquon on Fridays.