Ive had both for a couple years, here are my thoughts.
Pluses for Competition
-better turrets, great zero stop
-clearest and brightest
-amazing customer service
Pluses for VX6
-34mm tube gives great field of view. I find this very helpful for watching various conditions. Be it flags spread further apart or what have you. Lets you zoom in further but still maintain a wider view of conditions. Also increases ability to see misses. All of these have been major advantages for me. 34mm tube plus 42x magnification is amazing.
- maginification range allows it to be used in about any discipline. Hunting, PRS, F class, BR
Minuses for Competition
-none really but if it had a 34mm tube it would be the worlds perfect scope

-15x lowest power may limit its usefulness to BR or F class
Minuses for VX6
-turrets are not very solid and don't give a feeling of confidence in the unit.
-i Have several of these and I have had to send two in. Thats ok with me but Leupolds reps did not seem very knowledgable and I had to send one back a second time because it was not fixed correctly.
Just a few thoughts from someone using both.
-edited for something I forgot