I had a 10 " .. made a 12 ".. and have spent a little time with a few differant 8 's ... yeah apperture rules I guess .. ..
I'll tell you what I like /dislike about each.
8".. well its less apperture than a 10" or 12 "
.. whats good is it is very portable .. even the solid tubes are easily moved around .. I did chance a look at the lightbridge 8 a couple of years back and ok truss examples in smaller scopes are probably overkill but this was one very compact telescope.. sitting in a chair with scope on a small stool made for some pretty comfortable viewing .. same with an 8" portaball.. sit comfortably and you rotate the ball to bring the focuser to you rather than visa versa ..Despite the humble 8 " of light gathering I still think these scopes are still a dog that hunts very well.
10".. It gathers more light than the 8"
.... Yes the solid tube can squeeze into most back seats and you can cart it around the house and out back without to much drama (it is weighty ) ) ... it does take to bumps and bruises very well if you hit a wall or light fixture on the way I found
.. of course the truss build would be much kinder in regard .. One noticable differance in both the 10 and 12 regarding portability imo is not the tube but the base .. these suckers are huge and were always my major hassle when transporting .. dissmantle or have a car with heaps of room .. On a side note the 10 " base flipped makes a great revolving picnic table .
12"... It gathers more light than the 10"
.. most what I mentioned with the 10 " is slightly increased with the 12 "
I think It would be an ask to say navigating a 12 " base or solid tube through your home isn't without a few hiccups
occasionaly .. all are great scopes and will show you a lot .
good luck