Opinions On Silo's

Both brands that you mentioned are probably great. I have hunted not hunted over the Avalanche, but I have with Real Geese and some of the other brands on the market.
The Avalanche are the ones with flocking right? They are cool, but I am skeptical on the long range durability. Especially how I store my silos. I would think they would rub too much. The real geese are cool because the photograph on them is kind of 3D-ish. (A 2 dimensional decoy being turned into a 3) But I am not sure from my experience that this helps any more then not having that look. It might just make them sell better to the hunter.

Even all black homemade silos with white cheak patches and a little white on the tail area works. In fact Tim Grounds and Scott Threinen both say that the all black and white work better for pulling birds from farther away because they stand out better. Meaning they don't blend in with the field as much. I have no experience hunting "silos only". But I do know that it is done. I think I read once that Sean Mann says silo's only is his favorite decoy spread.

On another note, I personally have about 6 dozen silos. They were all made by me and my brother and my dad at one time or another. I simply got some wood from the hardware store drew some poses and cut them out with a jigsaw. Bolted some metal stakes to them and painted them up. These cost me (time not included) I think about $ 6.00 per if my memory serves me correctly. And it can be a fun family project. My wife, who is a vegetarian, even helped me make some about 2 or 3 years ago.

Not pushing any agenda, but Scott Threinen's new dvd: The Goose Society has tons of content on decoys, and shows you what the birds see when they look at them. He covers the silos in his talks as well. You might want to check it out. Another one is Top Ten Questions about the Canada Goose by Tim Grounds. He discusses decoys a bit in this DVD as well.

I use silos on non windy days (when the motion based full bodies won't move) as they can be used to create movement as the birds fly by. Mix them around and through your full body set up. The now you see 'em now you don't can fool birds to thinking they are moving around. They are also a great way to up your spread numbers to reach out to those far away to let them know you are there, without taking up a lot of storage space.

My biggest suggestion on any silo that you buy is get ones with the metal stakes as opposed to the wooden. I find them easier to get into the frozen ground.

One other note, check the internet. Some silo manufacturers offer rejects at a low price. A friend of mine bought a dozen real geese for like $50.00 plus shipping about 2 years ago. They had the head pattern and cheek patches in some of the wrong spots, but they still bring the birds in for him.
Hope this helps.