4wd system

Hello everybody.
I am an Spanish owner of a Yamaha Warrior 350. I am going to buy a new ATV, and I am currently deciding between a Grizzly 450 and a Kodiak 700. I have some conditions: I would like to have the EPS (power steering), and Diff lock. But the importer is not going to bring all the models produced in the US, so I will have to discard something. Otherwise, I would be decided towards the Kodiak.
I am very interested in this thread's topic, as I was just going to ask the same question as Zombies4brkfst posed.
So I would like to thank you very much if you could tell me how good is the Kodiak 700 transmission/traction system without the diff lock ON. The question is that it seems that the importer will not bring the Kodiak SE version, the only one which has the differential lock option.
Just to make sure I understand: when you get a wheel spinning without traction because of snow or mud, and you don't have the diff lock ON, do the other 3 wheels turn so you can get out of where you are stuck? Or all the traction gets lost in the spinning one? I have searched for a lot of information, but I stilll haven't found a conclusion. In particular, I would like to confirm what Ronbo says: that the rear axle DOES have a permanent left-right diff lock, and there is also some mechanism at the front.
In a different manner: do you find the Kodiak performs well without the diff lock option, in mud/snow conditions?
THank you very much in advance for your help. I look forward for your replies, so I can also soon become a proud Kodiak owner.
Regards,

Without diff lock, the bike is essentially a 3 wheel drive. Diff lock certainly has its place, but more importantly in my opinion is the proper selection of tires for the terrain you are riding in. Even a locker won't make up for bad tires. Only you can make the decision whether you really need a locker in the front differential. I didn't. I use my bike for work around my property and trail riding on logging roads. I don't ride in deep mud. The ergonomics of the Kodiak were more important than anything else. I could have spent another 700. for the SE but just couldn't justify that much more money for something I will never use. If you get into deep mud a lot, than a locker might be a priority and with that being said, I would look to a Grizzly. The Kodiak is essentially a smaller, slimmer Grizzly with milder clutching and no locker on low and mid line models. The shocks are also lower spec. But perfectly fine for the intended audience. The transmissions are and motors are identical other than primary clutch weights. Here in the U.S. the Kodiak 700EPS is the best dollar value and will more than likely satisfy most riders demands. Good luck.