If I get this wrong others feel free to say so.........
obvious differances are as follows
based on 801s (801 and 800 are similar BUT less reliable)
Big, heavy, 8" tubes, older, know to be dull low output - but not a problem in a dark room
701,701s and 708
Newer, smaller, lighter, 7" tubes BUT uses a large area of the tube and very close to the 801s for that reason. BRIGHTER I think
If you were looking to buy one I would suggest the 7 series, if you want an 8 series then the 808s would be better,
I own 2 of the 801s but only cos at the time they were available, would have prefered a 708.
for more detail and a tech answer search for the .pdf brochures on the net.
the 708 is almost half half the size of the 801s, 801s was the first simulator use projector as I understand.
800/1/1s style projectors will be cheaper than the 7 series
I have put a 701 against an 801s, Bought the 801s as I prefered the build quality and the large size did not matter.....
(refrained from childish size matters jokes

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