Not compared them directly, but have had my original 752s for a couple of years now. They're very detailed, open and dynamic speakers. The main difference between the two is the arrangement of the tweeter. The 752 has a mesh dome metal tweeter, the Freedom inverts the position with the bass driver to the top and the now silk dome tweeter below.
People often comment that metal dome tweeters can be harsh, or too bright. I disagree. I think you can say that about any set-up if you get the balance wrong between the separates. In any case, speakers with silk dome tweeters can be accused of brightness too, so this is hardly the preserve of their metal brethren!
To partner, if you go for the 752, I'd avoid bright sounding electronics and I'd look for an amp or source which has a good low end to it. I used to pair the speakers with a Marantz PM6010-KI, which had detail but not enough body to it. My CD player doesn't major on bass and the 752s have been accused of being lean, so you see the problem. It sounded good, but really not engaging.
One Sansui AU-717 later and we're on the money; the speakers really sing, music sounds very lifelike and the setup really delivers.
Hope that helps; incidentally, while the Freedom is meant to be the improved model, think of it as the same but different. The original 752 has its fans (as does the 753); both however, would be great choices and stack up well even 15+ years on.