So I've been playing EU III for a while now, and I would like to get a similar Paradox game. I was wondering if anyone could steer me right on this.

Should I get HoI 2, or HoI 3?

If I get HoI 2, should it be from Steam, or Gamersgate, where its on sale (albeit for the same price as the Steam version).

I like to play LAN games, but not to have to pay for multiple copies. I think the GG HoI 2 is DRM free, so maybe that's a better idea?

All help is greatly appreciated :P

I would personnally buy Paradox Games on Gamersgate, not on steam.

Now HoI II complete or Arsenal of Democracy ( the latter being a modified HoI II ) are very good games, have already gone trough quite a few updates. Arsenal of Democracy for instance covers the 1936-1964 period, has enhanced features ( higher resolutions, corrected game mechanisms ) and adds some interesting ideas ( logistics, intelligence) . Both HoII complete and AoD can be further updated to cross of Iron, that changes the map to make it a bit more like HoI 3, expands the period to 1933-1964, adds new technologies and unit types.

HoIII has a nicer interface, a larger number of territories and is a bit more complex. But on the other hand to have the full experience you should buy the sprite dlcs and the Semper Fi expansion. At full price, it's a bit expensive...

I would personnally go for Arsenal of Democracy as it is currently the best value for money. You may want to keep an eye on Gamersgate for a -60% o -75% promotion on HoI 3 .... That happens from time to time

Both HoI 2 and HoI 3 are primarily wargames, and therefore aren't all that similar to EU 3.

If that's what you want, then I'd advise you to get HoI 2 since HoI 3 is much more complex on the military side of things.
Then you have a choice between the base game or Arsenal of Democracy. AoD is better, but you can get about the same game simply by modding the base HoI 2.
If you truly like the game and decide to get Iron Cross later, keep in mind that last I heard, it had compatibility issues with AoD.

However, Victoria 2 might be a better choice, it's more focused on the economic side of things, so it depends what part of the strategy in EU 3 you prefer.

Either way, you should buy the games off Gamersgate imo, because that way you indirectly support Paradox. Still, it's your choice.

On the 29th March new game built upon HoI2 engine, Darkest Hour, is going to be released.
This one contains even the Great War.
Still as others said, HoI is mostly war game, it differs from EU quite a lot.

Thanks to everyone who has answered!
Just to make one thing clear...

I am perfectly happy with war games! I loved the strategy side of EU 3, but I felt that the war was still a little simple. I was looking for a game with with the same sort of look and feel, but more in depth with a certain period - preferably a later war (1800 <) - when I saw HoI 3 on Steam. I've been considering series since, and waiting for a sale on either game.

I already downloaded both of the demos, and I think I prefer the interface of HoI 3 better. But the demos don't fully reflect the in-game experience, so I was looking more of an in-depth comparison :P

FYI , HoI 3, the dlcs and Semper fi are currently sold at -70% on Gamersgate, sale expiring in 5 days something

Yeah, I saw that.
Thanks, though