what's a good autosomal match

[drogin]

I got a match at ftdna and gedmatch on my autosomal DNA, to someone who is confirmed to be half british and half ashkenazi eastern european jew.

Question is, is the match considered strong or good enough to be "real"?
It's 20.4cM, and contains 5040 SNPs.
Total of segments > 3 cM = 37.4 cM
Estimated number of generations to MRCA = 4.3


This is a picture of Eurogenes painting of the exact area where we match, spanning all the picture.
I'm the first one. My match is the second one, and the bottom is what we got in common.
http://i49.tinypic.com/n37qdf.jpg

[xajapa]

From what I understand, 20.4cM, and 5040 SNPs should be considered a real match.