I use these feeders all the time. I'm getting ready now to go on a weekend trip to New Hampshire.
We have two Lovebirds.
They use these feeders on the inside on the cage floor.. The other kind of feeders with the lids that they always advertise, the Lovebirds will pull the lids off and lean inside and try to eat all the seed.
This is the best kind I use. I might have to put two or more depending on how long I'm gone.
If you have large seed that you don't think will come through, you can always chop it up or grind it.
Some of the Love Birds' food has to be a certain size (no problem) to slide through.
Right now, I put one in the cage (they are still eating out of their dish) to give them practice and for me to see how
they are doing. I loosen up their seed and use these kind for larger birds. They like to tear apart lids, etc. The smaller birds (finches) will get the vacation feeders with the lids. They fly up to the bottom and eat. No problem with lids.