Winter sleeping bag

Most US Bags will be labelled 0*F, which is equivalent to what you are looking for
Good US Manufacturers: Western Mountaineering, Feathered Friends, Nunatak USA, REI, Mountain Hardwear, Integral Designs, Jacks R Better, The North Face, RAB, Montbell, Sierra Designs, and Big Agnes.

Most US sleeping bag manufacturers won't have inaccurate ratings of 0 degrees. There are 3 different types of sleeping bags, sleeping bags, top bags (no insulation on the bottom, just fabric and a pad) and quilts (which do not have any fabric on the bottom at all). Also you need to decide whether to get down insulation or synthetic. Down is lighter, packs better, lasts longer, but is not warm when wet, while synthetics do not loose too much loft while wet, and are inexpensive.

Other choices include
a lighter sleeping bag with insulating clothing worn inside
vapor barrier linings and clothing, that prevent your sweat wetting the filling, allowing you to be warmer and stay out longer.

Quick links
Sierra Designs Cirque 0' Reg Drzn 800 Down cheapest nice down I found
Mountain Hardwear ultralamina 0*, the one 0* bag I have experience with

Thank you for advice!
I check brands you recommend me and think about ordering of one of this bags: Western Mountaineering Kodiak MF or Western Mountaineering Puma MF.
(I'm not a small guy – 6'4", so I believe, that one of that sleeping bags will fit me good.)
Do you have any experience with any of them?

Anton, you can't go wrong with any of the Western Mountaineering bags. They perform to spec and are built to last. I've had the Versalite for the last few years and it is going strong!

Since you are not in the U.S. and live overseas, you may also want to consider Valandre bags. I imagine that they are available where you live. They are quite lightweight and use a very high quality grade of French Grey Goose Down.

Disclaimer – I'm an authorized retailer for Valandre'.

Only way i am affiliated with Valandré is as an happy customer.

I dont see the point of their duck down bags, they are pricey for what they are worth.

But their goose down bags are great if you can/want to afford them.

My wife and i owned 4 valandré bags ( 2 are sold ) and 2 triple zero bags.
TZ down is at least as good as Valandré's but the enveloppe is less elaborated.

If money is no object… http://www.phdesigns.co.uk/product_info.php?cPath=23_91&products_id=244