Opening of the funnel must face up, pointy side down.

From my perspective, having the same location is also no issue and not making it boring.

-The change I would be looking for is your body.
Shots of the belly before and after eating.
-The numbers on the scale: how much did you get in (and looking for a new high score )
- Seeing your strong willpower during a stuffing (changing positions to get space in the belly again, standing up at the end to fill the rest) - that's a sensation to the viewers.

That's what made the kebabqueen videos so beloved by the way.
When you thought that's impossible, she kept on pushing. The belly visible distended at the end - that's big cinema.

... today night (means in about 8h) I have some free time and I'd like to check my capacity limit

Who's up for a chat or maybe a parallel stuffing to compete and encourage and pushing?

Yes, I do that, too.
Motivation is for example the willpower and endurance of this lady:
yewtu.be/channel/UCows7epPEd0REdNHr2bXHXA

That's a very good point - and a good example that by "pushing the limits" some of us refer to a casual event of pushing how much can fit into the body at once - and others push the limit of how much can be gained (and kept) in the shortest period of time.

But what makes us want to push the limits?

For me (as casual stuffer without wanting to gain) the stretched-out feeling is like winning a sport and some kind of sexy.

What makes you do it?
(Especially to the gaining department, as I can't feel into that but would be really interested to know)

... and how many pounds or kilos of difference before/after do you reach?

I like that kind of stuffings (food and water), too - the feeling of the rock hard belly is absolutely fantastic

You don't need to waste food If it doesn't fit, just take some time, relax and let it settle, and then eat some more until it's done.
I would bet you can do it.

Most efficient way is to stretch your stonach regularily and have it used to reach the limit many times.
Have a big meal until you can't fit any more bite, then wait about 10min and try to drink ½ liter, even if it takes a long time.
Or even a liter once your belly got used to it.

Or pushing the speed limit on the way to the restaurant!

Absolutely same here!