yes, i already have the threadless steerer. the bike i'm adjusting is a new touring bike - made for me and fits me well, except i'd like the bars higher (my lbs screwed up and cut the steerer tube). since it's a touring bike and not a racing bike, comfort is more important that speed - hence raising the bars.

i've read reviews for the various extenders, but i'm looking to you all for opinions on what's worked best for you.