There is "tie bar" on the loader side to help keep the shoes aligned, but yes the structural integrity comes mainly for the attached implement. This is not unlike a SSQA setup in this regard.
It is. It's easy, fast, and most importantly VERY light weight so it's ideal for the smaller tractors.
Maybe on the used market, but there are new items readily available from Frontier, Artillian, Everything Attachments, one importer of Chinesium stuff I won't mention, and other quality manufactures.
The reality is that on most sCUT's and CUT's there are really only three things you can effectively use, a bucket, some forks, and a lightweight grapple. Most all SSQA stuff that everybody says you can find cheap and interchange is really not usable due to the lower lift capacity, lack of hydraulics (or insufficient GPM flow if you have a 3rd function), or lower overall machine weight. Yes you can buy SSQA forks on Craigslist all day for ~$500, but they are usually 400 pounds and beat to crap.
Sorry for rambling a bit...