I purchased this game at the 2013 Xmas sale, but didn't play it right away. The game has since been included in a Bohemia Interactive Humble Weekly Sale, so the game may have gained a number of players since its release.
It always saddens me when I have to write a negative critique about a GNU/Linux game (even if it's a proprietary one), but this game was very buggy and really left me with no choice... so here goes it.
The first problem I noticed was when tossing a grenade from behind cover. Although the line indicating where the grenade would be thrown looked fine, the grenades would always hit the cover you were behind and you would blow yourself up. By the time I completed the game, I had probably killed my team members with grenades more than the enemy. Needless to say, I didn't use them much.
Shortly thereafter, I discovered that I wasn't unlocking any Steam achievements. Some people in the forums indicate that they also have this problem occasionally, but even though I completed the game I never obtained a single achievement. I personally like collecting achievements so I found this particularly frustrating.
Completing the first campaign (out of the two included) didn't take very long. After completing the last level of the first campaign, the stats screen appeared (as it normally did at the end of each level) except there was
no Continue button. This made sense since it was the last level, and it still had two other buttons - "Restart" and "Main Menu". Clicking Main Menu did absolutely nothing. I didn't want to restart, and I didn't want to lose my progress, so I did the only thing I could immediately think to try ran the kill command on the game process ID.
Unfortunately, that didn't save my progress either. Possibly a SIGQUIT instead of a SIGTERM would have been better, but in any case I had to replay that level from scratch... and when I completed it a second time I had the same issue reappear yet again! This time around I pressed ALT+F4 to close the program, and that command did enable the game to save my progress and unlock the next campaign. Presumably ALT+F4 is the equivalent of a SIGQUIT.
A couple of levels later and I came to a mission whereby I was instructed to send two soldiers to one exit on the map, and two to another exit. I tried this many many times, and every time the
level would freeze. Not cool. Eventually (searching through the game forums) I discovered that the only way to complete the level was to ignore the mission objectives and just kill everyone on the level. That wasn't hard, but it took time to find some of the enemies hiding and it was certainly not obvious that doing this would have any impact on the game not working.
One other problem I noticed throughout the entire game was that sometimes the lines which indicate how far you can move in a turn
would not appear. Sometimes they would be completely missing, and other times just part of the lines were missing. This was certainly an annoyance when it occurred, and by the end of the second campaign it had happened a lot.
The last annoyance that I'll write about here was that the soldiers would often not do what I wanted them to. If I only wanted them to move a tiny bit, and next to one of the other soldiers, the soldier I was commanding would more often than not heal the nearby soldier without moving at all. In later levels where mortars can take out multiple soldiers in close proximity, it's can be very difficult to select the man you wish to revive. The mouse just didn't seem to do what I wanted it to do when the soldiers were bunched together, which only added to the above frustrations.
In summary, this game is seriously buggy. Due to the massive amount of bugs you will certainly encounter, this game is stripped from much of the fun that would normally have been enjoyed. Even if this game was bug-free, this would not have been an amazing game (it doesn't have multiplayer, there's not a lot of depth, the enemies are really stupid, you can easily miss shooting somebody standing right in front of you, etc.). Even on the GNU/Linux operating system, you could likely do better than ARMA Tactics for a turn-based game. eg.
Expeditions: Conquistador looks like it could be good, and of course there's always
The Battle for Wesnoth.
The bottom line: Steer clear!