Room size is definitely a deciding factor, the difference in size and weight from a 1961 to a 1723 speaker is quite big.
Sound quality is also a deciding factor, I’m sure 1961 speakers will sound good but 1723 are certainly superior and more detailed.
Lastly it’s also a feeling thing, a 5.5″ driver can reproduce bass notes quite well but you can only hear it and not feel it, a 8″ driver will go deeper and more importanly you can feel the bass notes in your chest, you have to try.