I have a Mk1.
Pros are: Super light weight. Good pan and tilt. Easy to use. Real quick attach and removal.
Cons are. Legs have no stop (they will come completely out if your not careful). Tilt screw needs a lot of tension to lock up fully and maybe a little more height would be nice.
Moved from a Harris. So far though, I think the Javelin is better than the Harris and the Mk2 Javelin should be even better.
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