I'm new to the forum, but i'll chip in my experience.
No comment on Rome since I never rode it.
I learned snowboarding with a 2000 model NS Premier. The board at the time was too much for me to handle. But once I got better, the board flies. The basic speed for this board was fast, faster, and fastest. Its built like a tank and very stable at high speed. The ultimate downfall for me at the time was the weight of the board and the board was too aggressive and unforgiving. I wanted a more rounded board.
I moved on to Nitro Misfit after that. Misfit was a great all mountain board. It was lighter then NS, super maneuverable yet stable at high speed. I prefer the misfit in the trees more then the Premier. Another selling point was the width of the board. I wear size 8 us boots, and its hard to find a board with a narrower width (especially every year the board seems to get wider for whatever reason). Nitro does have regular and wider boards which was a big plus. You also can't beat the brass knuckle they have at the bottom of the board. I did demo Nitro Team. While it rode amazing in the trees, it was not stiff enough for me on the groomer and chattered the whole way down.
Now I'm moving back to SL-R 155 for my powder stick and Evo 151 for my everyday. Love the board, but I wish they made the SL a little narrower. Although the width is amazing in powder.
I demoed a few other companies in between. While they were good, I just loved Nitro Misfit and Never Summer. You can't go wrong with those. In retro spec, I would not have learned snowboarding on Premier. It was too big of a leap and a constant edge catch. But the R.C. tech is amazing so starting on the Premier-R might not be so bad now.
For bindings, I love my FLux (older model....because frankly, the new model graphic is just bad...)
Big sales IMO starts in Mid-March. But as far as I know, NS this year is going to sell out. Evo and SL are almost already gone completely.