I've put my 2 budgies in the big cage with Obi....
I'm trying to cut back on cages to clean....
So far it's ok only been 48 hours yet.....

Hope it works out! When I started out I had to move the budgies away from my canaries and zebra finches (Didn't have cockatiels at the time).

Even now I see they don't always get along together...

Sometimes cockatiels and budgies can get along very well together and sometimes they can't. But when they can't you usually see the problems pretty quickly, so it's a good sign that they've lived together peacefully for 48 hours!

They are all doing great....
The budgies are very laid back.....
The tiel is a nice peaceful bird so fingers crossed...
Much easier doing the big cage then individual ones....

I did something similar. I got rid of the biggest flight cage and now have a large and a small vision cage. The budgies and cockatiels are usually all in the bigger cage but sometimes one or two will use the little cage. It is much less cleaning. The vision cages are good at containing the debris. The budgies sometimes annoy the cockatiels. But, now they have the swings over the cages up high, so everyone has a place to get away.

Glad to hear it's going well for you! I have housed budgies and cockatiels together in an aviary since I started keeping birds about 15 years ago and have little to no issues. The only issue I have found is that budgies can be a pain when it comes to harassing everything during Spring