My advice would be to go for the B1, or even the B2, as always it's best to demo first if you can.
Last season I demoed the B2's (they didn't have a B1 available and as it turns out that was just fine) and and Super Sport 5 stars. I preferred the Rossi's. While the 5 stars were better at carving they lacked the versatility of the B2's, which carved pretty darn well. The 5 Stars were simmilar to my skis (Atomic Beta Race 9.20's) in their ability to lay them over and carve and rip off powerful GS turns, I found them slightly more forgiving than mine, but less powerful and they had less rebound energy. My skis are great for carving (which is what the 5 stars are designed to be good at too), but aren't the best choice in the bumps (too much rebound energy and can be a bit too turny), or in powder/off piste. This also seemed to be true of the 5 stars. The Rossi's on the other hand gripped and carved pretty well (I'd give the Volkl's an 8.5 out of 10 compared to a 7.5 for the Rossis in this category), could handle speed (though not quite as well as the 5 stars), and were much happier in the bumps. I also expect that they would do better off piste.
If you're looking for a great ski for carving and are a strong technical skier the Super Sports are a good choice and should definitely be on your short list to demo.
If you're looking for a versatile all mountain ski that handles the bumps well and is forgiving of lapses in focus (no worries if you get in the back seat from time to time), then the Rossi B series is definitely a good place to start your demos.
I'm a pretty solid technical skier (I actually enjoy taking lessons(upper level group lessons are usually private/semi-private) and doing technique drills (I'll spend 10-15 runs a weekend on that)) and ski bumps about 40%-50% of the time. I love my skis, but I bought them not knowing how much things had changed (they were my first skis since 1986 when good skiers bought consumer versions of race skis for all mountain skiing), they excel at their intended function (carving medium radius GS turns and hauling @ss), they're not bad in the bumps IF I'm on my game (if I get in the back seat they will launch me), and they're definitely not meant for off piste. The 5 stars seemed very simmilar, but less powerful. Between the two, I'd take the Atomics. On the other hand the the Rossis weren't as good at carving, but were much better in other areas and more forgiving, between the Atomics and the Rossis I'd go with the Rossis (or something simmilar).
That's just me, YMMV. Check them out, they're both very good skis, and very different.