Have researched 37" TV's to death and have narrowed down to Sony KDL37EX503, Panasonic TXL37S20B or Samsung LE37C650. Might there be a massive difference in terms of picture quality (particularly SD freeview) or would each of these potentially be a good buy? Quality of sound is not an issue, and I nearly bought the Sony before reading suggestions that the 37" version of this model is not as good as the 40".