[Gorloth the Great]

Do kos work well agianst a mechanised IG army.

[Yriel of Iyanden]

Hmmm...could we qualify the question a little more?

If you ask me- Kult Of Speed has a decent shot of beating any army, mechanized or not.
What type of army are we talking about specifically?

[redbeard]

KoS can work well against mechanized armies. It can also fall flat on its face. You have the potential to take loads and loads of anti-tank weapons. Rokkit buggies, zzap trukks, mobile tankbusta mobs, and the like. But, you have to actually take them. A KoS army fielding loads of trukk boyz and skorcha buggies is going to have a hard time against any sort of armour.

The one thing to remember is that they're most likely going to out-range you, so anytime you get shots on them, make sure you kill what you're shooting at, or it'll shoot back with a lot of shots, and probably pop your vehicles.

[Gorloth the Great]

an imperial guard mechanised that has no fast attack and a lot of storm troopers and tanks. and since I'm not a experienced ork player would i have a good shot of winning.

[redbeard]

In general, I would say that inexperienced players have a low chance of winning against experienced opponents, regardless of what armies they play, and about a 50/50 shot of winning against other inexperienced opponents.

The less you know, the more luck is a factor in your games. The more experience you get, the more skill you will be able to exert.