My experiences w/ my SA striper line match yours exactly if not more so as I am not a good caster.
Its great stuff on a flat calm day, when I'm perched up on the bow of my boat, line nicely looped in wide coils at my feet. Its a bitch in the stern of the boat when the seas are tossing and I'm dropping it in a confined space so it tangles.
I have the same feeling about wading w/. it as you - its useless w/ a basket as the basket forces the coils tight and tangles invariably result.
I guess my summary is that as advertised - it will add 20 feet to your cast, it does to mine,but..under normal casting conditions, surf, wind, current, etc. you tangle 20 feet short of the amount of line on the deck so the end result is a cast of the same distance as the old normal Cortland style line.
One thing in the SA stripers favor is the ease of shooting 40-50' casts. The heads about 30', there's 9 feet of line in the rod, so its easy to add another 10' or so w/out a tangle.
And as we all know; if your thinking and reading the water, a 40' cast is plenty in 980% of the situations.