It is not a bad movie, though it is
not an action movie. Thus, if it is advertised as one, it is incorrect. It is a war movie, it tells a fictional story of a machine gun platoon and company from 1941 to 1944, a long period of time.
My opinion on all three films are:
Tuntematon sotilas (1955): the "original" version. It is a Finnish classic. I first saw it when I was around 8, I think. This movie is shown on national television on every December 6th and to many Finns this is
the version. Personally, I feel this one is most loyal to the original novel. Action scenes are not particularly impressive, but the feeling the atmosphere is there. Pacing is fine, between battle scenes and times of relative peace. Even though the movie tells a grim tale it is at times humorous and even optimistic.
The first
scene is touching:
Finlandia playing as decimated MG platoon is retreating across Ladoga Karelia and the few who remain carry their wounded and deceased across a field.
Tuntematon sotilas (1985): I have only seen it a couple of times. Compared to 1955 version, this one is much darker, grimly realistic in its approach. While 1955's version is more positive and happy, this one is pessimistic. The horror of war is shown more than in 1955's version. Many scenes that make 1955's version lighter are missing or understated. Of all three this one is most a
war movie.
Tuntematon sotilas (2017): It is of course a product of a different era. Graphically it is more impressive: scenes are well made. Though I can't help but feel that this movie is at points more about corporal Rokka than the entire MG platoon, like older version were. It is not necessarily a bad thing but at points stands out.
This is also the only version that shows the home front. Earlier versions concentrate on the platoon itself while this one shows scenes like Rokka seeing his family in Karelian isthmus or Kariluoto visiting his fiancee just before the star of the war. It adds a different depth to the movie compared to others. Personally I think that the best version of this movie is actually the TV series version. It is even longer (around 90min) but gives even more depth.
All in all, while they all tell the same tale, they are very different movies.
As movies I'd rate them like this:
1) 1955
2) 2017
3) 1985
All three have their strong and weaker points but in the end it's hard to beat the classic.