I don't have CrossClimates, but General Altimax AW365's
Are they better in wet weather? Yes - they are "stickier" than the stock Michelin Energy Savers, and have performed better than other all-seasons I have driven
Are they better is slush? Yes
Are they better in light snow (up to a couple of inches)? Yes-ish (in other words, they are better than all seasons, but not really in a "where has this tire been for all of my life" way)
Are they better in heavier snow? Nope
Are they better on packed/icy snow and ice? Nope. (but the directional stability is excellent - you slide in a nice straight line)
The "cost" of this better traction is a bit of fuel economy (probably about 5% during the summer months, but you make up some of this in the winter months) and durability. The softer rubber compound that gives the better traction wears quickly, so if you get all-weather tires, plan on replacing them a lot sooner than you would with all seasons - think in terms of 40-45,000 miles (68,000 km for the metrically inclined). You might find all-weather tires to be a bit noisier, and you may also find that your handling/steering response isn't quite as crisp.
Would I buy all-weather tires again? Probably not - largely because the wear issue really outweighs the extra traction.
The idea behind an all-weather tire isn't bad, I think it needs a bit more refinement.