You are all across the board performance wise. Rossi BC series and T-4s vs Siderail/Vectors/vipecs. The The Vector/Vipec combo is stout enough to survival ski anything, and have fun on most things.
I own Vector BC's mounted tele. It is an awesome rig. There is very little I can ski that I can't ski with them.I use my T-1s. I have also accompanied recreational cross country skiers on maintained flattish terrain. And I walk the dog out my back door and link turns back to the house. But, as soon as you go tele, you give up light weight.
Boots- I ski Skookums for lift serve. If your feet like Skookums, it can be tricky finding the right boot. FWIW, my light BC boot is La sportiva Spectres. First Gen was narrow, these are not. A boot with an easy tour mode like the siderail would rock with this set up. If the new Siderail fits like the Spectre, you should be able to make it work.
Bindings- With the fishscale ski, the Vipec is a great choice. Easy ski/tour/ski switches, as opposed to Dynafit. IMHO, worth the weight penalty.
Personally, I love my T-1/Switchback/Vector BC combo. Being able to ski with boot/binding in ski mode, then shuffle a bit with no adjustments works great for the type of exploring I do. Dense Maine woods- link 3-4 turns, traverse a bit for the next opening.... But they are tanks compared to Spectre/Speed Radicals/carbon converts. If I scaled the ski down to the next width down BD carbon ski, the difference would be even greater.
If you want light and versatile.
Race type AT
Lightest binding with easy ski/walk/ski
I would also look at the V6 bc.