Sideshow Collectibles used the MOW jetpack. On their website they claim the replica is in total 6' 6.5" ...Now you can assume by looking at the pictures that the base he is standing on is between 5 and 6 inches making the actual Boba Fett somewhere between 6' and 6' 1" If you ask me the MOW jetpack looks like it is a very good scale to the original, Jeremy Bullock the original actor was noted to be 6' 0" while filming Empire Strikes back.
Anyways, I am 6' 1.5" 200 lbs and I also have the MOW jetpack. In person I think the scale for me is perfect. This is the research I did before purchasing and I can vouch for the quality of Christians jetpack. Very easy to assemble and very minor prep work needed for painting.
Hope this helps brother!
-Cheers