Our church uses the International Children's Bible, but our Friday Bible study class uses the 1984 NIV (will be changing as the 1984 has been replaced by one that won't work for this class), and then we mostly have the Holman Christian Standard at home that we use (and is also the version our sons use for Bible Drill classes, which they participate in Sept.-April culminating in a Bible Drill).
Good news (no pun intended) is that they have grown I think by being exposed to different translations. My 13YO said recently he really liked studying with the KJV, and we have several copies of that as well, so that is what he uses often for personal study.
I used to be an Editor for a major Christian publisher of Bibles, Bible studies and books, and I had to proofread the Bible passages word for word, comma for comma, space for space ... at one time I had 20+ different versions, but I have culled them out since I no longer have this job.
I prefer HCSB or NKJV myself. Well I like NASB too ... OK, I like using multiple versions on a regular basis for in-depth study as well as Strong's Concordance.