I'd like to buy concrete gringing equipment but don't know witch are the leading manufacturers, please advise All i know is EDCO, are you familial with it ? Thanks

magnum , core cut ,target are just to name a few but edcos are usually a pretty good machine I have used them quite a few times

If you are doing some serious grinding, check out Husquvarna.  Last April I was working for a company that used Husquvarna grinders to prep 14,000 sq. ft. of floor for a local church. Check out there website, if you have trouble with that, let me know and I can get you the name of one of their local reps. They have a location here in Kansas City.

Blastcrete

what about MQ (multiquip)?