I've had some for a year now- there appears to be not alot of current interest/value.
I don't exactly understand why. L-L/N is the only avail means of having a 2 letter combo, ( of course, "-" is a char- there are no 2 char .info/biz/us).
I recently had 3-X.info/biz/us up Afternic Bazaar- they were expiring so I renewed them and settled on a price of $15/ea (ie $7.50-orig regfee = approx $2 profit), and the guy backed out, because he didn't want to pop for the $9.95 Bl Razor fee, which I had not included in the description.
3-X isn't great, but it does have assoc and could be used in branding. So, that is a current, real world experience regarding the state of affairs for N-L info/biz.
L-L and N-L combos that I have and that I believe are worthy of holding onto for a few years include:
K-O, K-9, B-X, V-P, S-W, U-2, 4-4, Q-Q and 1-A, (Duke beat me to the punch on A-1). Despite their having some distinguishing characteristics, I am letting a fair number of weaker ones drop, because of my portfolio depth and the %/number of names I am willing to carry for longer term investment.