Anything I should know about the 2011 cube
or anything I can do about the road noise

I think the road noise is usually caused by the mirrors...sometimes it's pretty painful between LA and PHX haha. The windshield is almost 90 degrees so that assists the noise LOL. However the Cube is a nice, roomy, reliable and unique car. Watch out for the front pillar blind spots in intersections though (dip your neck on both sides when people are crossing). Overall though, the car is fun to cruise around in and definitely saves your wallet. (I used to drive a limited edition GTI...it cost a pretty penny for maintenance. I carried two wallets bad am pam ching. Ugh.)

2010 SL see my thread "Transmission and gas gauge problems". Bought certified used 13K mi on it, now 23.5K mi on it absolutely love it. Fuel economy great, 75-80 Interstate 26 mpg, 65-70 30 MPG, around town & highway 31-33 if I don't jam on it to much. I replaced the OEM Toyo tires at 20K miles with Fusion tires made by Bridgestone. Made a wold of difference in the ride and handling much softer ride to. Toyo tires wore out way to early for me and I don't drive it that hard or corner fast. Wife drives 2010 Corolla 26K miles on it Good Year Eagle tires on it have about 10K miles left on them much better than the Cube Toyo tires.
Dealer told me Nissan designed the Cube for the "younger generation", but to their surprise it is being bought by middle age and senior citizens. I like it because easy to get in and out of, comfy seats, adjust any way you like. Mine has the back up camera and Rockford stereo and sub woofer, I put on JIMI HENDRIX or LED ZEPPLIN, kick back and relive my exciting flower child hippie days. " 'Scuse me while I kiss the sky . . . . ."

For the wind noise, buying windows visors help a lot to kill it. I doubt it back then but after getting a set of AVS last year I was wondering why I didn't got them on day one.