Show of Hands?

Hey, I feel ya, man. As you know, for me, it all depends on the context and the story that's wrapped around it. There are difficulties with boobs the size of basketballs; also, difficulties with ones the size of cars! It makes for a good yarn.

There is absolutely nothing in the world that can't be fixed by a bed made out of boob. :P

I think you said it there. It's a fun size to work with because of these reasons (Down to her knees and so many feet in front of her body?) Forget driving and standard-issue doorframe. But yeah — there's something I love about the aftereffects of this crazy kind of expansion, and how it affects the woman's life in the day-to-day. No spoilers, but I've been harbouring a story for years about just such a thing... group of friends, they all underwent this crazy expansion, and are just trying to live their lives in the aftermath. Hopefully it'll end up here once I flesh it out and write it down!

Giga because she is still mostly capable of moving on her own but still feels the effects of such massive boobs - like getting stuck in small places, not being able to do things because theyre so big, difficulty walking/moving quickly. Giga is the biggest breasts could be and still retain something of a "normal life" and one of my favorite aspects of BE is what happens after the BE, how does life change?

XtheTank

Giga to zenith is my preference especially size of kinda overboard but not touching ground could be biggest size yet still can move by self. but also love zenith size boob bed too.

I know this is a cliche answer, but I like pretty much any size. If I had to narrow it down though, I'd say Massive to Xtreme would be a good typical maximum. Of course I wouldn't say no to Giga or above, but those sizes would either need to be earned in story, and aware that diminishing returns are a factor. If every woman grew to the size of a pair of Suburbans, then it wouldn't feel as special, you know?

Antares

Haha! I get ya, bud! Logic.

Somewhere between huge and massive is my go to because I want a functional girl still xD

TheDarkOneZK