I finally decided to try 5 Core (second edition) from Nordic Weasel Games. And, unfortunately, I have to confirm what other people already stated on the web - 5 Core is the best SF/modern skirmish game available on the internet. Didn't expect this to happen - but I am totally hooked :)
For my first game I decided to start easy. There are many ways to customize your character in this game, but I just took 6 grunts per side and went with it. I played orks (2 teams of 3 soldiers, with normal grunts armed with sub-machine guns, and support consisting of one auto rifle and one grenade launcher) while automated side consisted of space marines armed with infantry rifles and supported with 2 auto rifles.
Terrain is set as per Control the river scenario from One-Hour Wargames book, I just added more terrain peaces on both side of the river since 5 Core asks for dense covered table.
Game was played on 1"x1" table using GW Epic 6mm orks and marines and 1'=3' ruler.
Marines rolled for behavior and got Aggression level 6 - very aggressive, and their priorities were to advance on enemy positions.
Marines tried to do the same on the north, but they fared even worst - one marine got out of fight and one bailed.
To the south, two well placed shots from grenade launcher killed two marines (one with auto rifle).
Outnumbered 5 models to 2, marines decided to quit the field. It was middle of the turn 9.
This was incredibly fun game, and I can't wait to try it again. The very important for the overall impression is the fact that all your actions are very logical. You should know what you want to achieve in every turn, so you can decide what you gain if you take a risk and is it worth it, and based on this you make your choices.
But you really have to play this game and feel it - I never expected this just from reading the book. So go ahead, and try 5 core.