This is almost always the first "gem" of advice hauled out (pun intended) regarding 8x10s and it is patently false. I've played several different cab configurations over the years, and the 8x10 was by far the easiest transport. Two 4x10's means more trips and you're more likely to be carrying them by yourself. Then there's skinned knuckles on doorframes from side handles and the extra factor of structural instability. On a lot of wobbly stages, you can take the head off the top of the cabs, but you rarely have space to place two side-by-side (and doing so negates most of their acoustical benefit anwyay). So, if you have need of 8x10 volume, you're no better off carrying smaller cabs just for the mythical 'ease of transport' factor.
A huge +1 here. I'm using a 4x12 which is even nicer to transport since it has the same great form factor but is 65 odd lbs lighter! You just need a pickup, van, or wagon ... then the fridge is way more portable than a 4x10.
I'm a recent convert to the fridge format and can't see going back. Now I want an SVT cab! I've always used this many speakers but it was always a two-cab setup. An array of speakers about the size of an 8x10 is simply the scale our instrument exists on. A small, loud, point source doesn't sound right to me. More speakers, less overpowering = better tone IMHO.