I am a "newbie" and after trying to do a ton of research I have jumped in to finches with both feet

Currently they are housed in a Prevue white aviary that is 37L X 27W X 68 inches high
Everyone gets along although the old adage of getting the biggest cage possible is so true. I am out of space.

Somehow (with a bit of subtle prodding) I have convinced my husband that I need a bigger set-up.He surprised me yesterday with an early Xmas gift of two spice finches which are currently being quarantined in the cage that I use as a hospital cage. I am worried that adding two more to the mix will not be a good idea as space seems to be at a premium. After much web searching I have found what I think to be the answer.
A&E makes a hexagon corner aviary called the 100G. The large size is 52L X 42W X 74 inches in height.
Any ideas as to if this will be big enough for now the growing flock of 10 ? I am very excited about the possibility of having enough space that everyone can fly and feel that they can claim their own space.
One review of they aviary I'm now considering was from a woman who has 20 budgies in it. That seems excessive to me however, according to her review they were very happy. Does anyone have this product ?
Please advice

Thank you,
Jennifer