Necro'd a Necro, nice!
It's definitely worth buying, but don't get it from Steam, pay the
$9 to get the DVD off Amazon or something. Steam has a lot of problems with regards to modding, and modding is ESSENTIAL.
Many of the bugs that plagued SH5 way back when have been fixed. The modding community has fixed many more and improved and expanded the game into a very playable and enjoyable state.
Ubisoft has basically completely abandoned the product. You do still need to log in online to start the game, but you no longer need to be connected constantly to play it.