I had mine replaced last year. If you've ever seen the instructions on how to go about replacing a soft top, and have never done anything like it before, you better consider having someone do it for you!! Especially if you want it to look good and fit properly. It would be foolish to spend $300-$400 on a top, do it yourself, and have it look like crap and possibly leak, on an otherwise nice car. I had mine installed by a professional upholstry shop for $800. I didn't want to spend the money either, but it's not an investment that I'll have to make again for a long time. Check out this thread for installation instructions:
http://www.worlduph.com/mbtopinstall.htm
Best of Luck. BOB