they're pointless compared to waves plugins which duplicate the performance exactly, if you already own waves plugins of course. if not then they have their points I guess.
There are WAY better sounding mastering plugin collections though compared to the sound of a maximizer.
maximizers are well made and look cool and can sound cool but they really aren't justified compared to much more convenient plugins that sound the same these days.
I would use one for a tracking mb compressor though just for the hell of it. at mix I just use plugs these days cuz they're so amazing compared to plugs of the past. I don't even use otb verb any more, and I own 1176 comps and some pretty amazing outboard. Unless I'm being paid specifically to patch into a given outboard setup in which case of course I'll use it and very happily, I love real gear. but it's easy to get used to plugin automatic recall and forget to write down settings of everything and keep it all organized...
I forget the plugin collection I use for mastering but I adore it. I am NOT a mastering engineer, but for those frequent low budget or rushed times when I have to play that role, the toolset I use it a godsend. oh yea, T-racks. I loved early versions when everyone else hated it LoL (they prob used the presets...). Now it gets adoration for the quality of it's compressors and eqs and the great tone they have, and I still love it and it still sounds great to me. also terrific as individual plugins during mixdown, or the whole suite on the vocal busses. blows away any maximizer type of product.