The glass dosn't matter tooo much. You don't want your lights that close to your plants anyways. I can get my hoods 6" from my tops and keeep leaf temps in check but I would never do that anyways as you will basically fry the shit out of them.
Reflectors are not just "reflectors" Believe me when I say that the probability that your hurricane lantern thing actually sucks dick is very very high. Reflectors are all about the shape and how they reflect the light in terms of eveness and intensity. Two hoods that look similar can have very different light patterns and effectivness. I have done A LOT of testing of different hoods and set ups. Cool tubes actually score very low on several websites that have posted results becuase their hood shape eats dick ITs comical really, about 30% of the bulb or more is not even being reflected.
If you really want to know the best hood for a 4x4 its the blockbuster 6. Hands down. I was soo impressed I bought 12 of them after using one for a grow. high quality, good size, great seals, just super hoods. And they tested really well.
google greeners AC hood review or air cooled hood test. there is also a great thread on ICmag with cp readings and patterns from different hoods.. its like 100 pages long.
I'm all about vertical after the last grow though
NO hoods, no ducts, no dirty glass, no fucking fans. Just lots of bulbs, huge AC and 2 lb trees. Again, not for you but its a good way to go in legal states.