I've only played Hotel Giant and Transport Giant, but both of them are pretty bad. Hotel Giant in particular is excessively simplistic and easy to win, but still manages to be a pain in the ass to navigate. I never bothered much with Transport Giant because, even when running on a PC in its era, it still crashed so often as to be unplayable.

avoid them if possible , their first games in the series may be addictive and simple but the rest of the games are the same rehash of previous games.

Industry Giant 2 gets published these days by UIG and shouldn't be confused with the newer Giants. From looking at the farming games, I got the impression that they are more about simulation and less about management (if I remember correct one version emphasizes the management more, don't remember which one).

Thanks guys, I'll avoid them ;)