I don't now how anyone could sell the Okna and actually lose money doing it. That price is impossible.
The soft lite Imperial sounds pretty close and a good price.

I assume that this is window only, no install? The okna is flat out better than the standard Sunrise, and very comparable to the imperial LS ( although I'd still choose the okna all things equal ). You'll get a better u value, equal or better air infiltration, and more glass area. The fact that it is cheapest is a major bonus... Although I agree with mmarsel's, even for a cash and carry window that price is crazy low.

That's what mean, just the Okna window itself( without install) cost much more than that.

That was a no installation price. Assuming the Okna was higher and the same as the Sunrise would the Okna still be your choice or at that point go Soft-Lite?

Yes, the Okna is definitely a better offering over the standard sunrise.

Let me just say this, you are looking at three great options. You really won't go wrong with any of the three. That said, my assessment above is independent of pricing. The softlite and okna are both a step up form the sunrise in double hung form, and my own personal preference is the okna.
One thing I didn't mention earlier is that it can vary somewhat once you get to casements. The sunrise casement is probably the nicest, followed closely by the okna and then the softlite. The softlite has the least amount of glass, which is probably the only real knock against any of them.

+1

You have 3 great options there.

That price on the Okna is crazy low. That is below cost unless they are moving a ton of units.

How are you getting that price? Do you know that vendor personally?

The Okna is a heck of alot more than 250 per window..it is way under cost...I'm completely baffled by this price.