Hi,
Yes, I've been certified for 1 1/2 yrs. You definitely need to get the LPN/LVN study guide - go to the HPNA website and order it if your organization doesn't provide it. I think there were a few simple calculations, but I'm not positive. What did surprise me is the number of odd questions they asked - it didn't seem relevant to either an LPN or RN's practice. Lots of psychosocial questions, too. Overall, I don't think the test was very difficult, just "different". Similar to state boards..
Good luck!
mc3