I think we should have a separate thread on growing trees from seed. I know there have been several threads started but it might be a good idea to keep them all in one place.
I grow a few hundred trees from seed each year and have tried most methods/pot styles I have come across. I typically grow chestnuts, hazelnuts, oaks, and persimmons. Even though I know things like the bin method or building custom air-pruning boxes are easier and at the same time more effective, I still like to try and grow some from seed indoors as a winter project. Also, because I live so far from my property, it is nice to have a reliable container to move plants safely to the field. The deeper tree tubes from greenhouse megastore work great for oaks, but the carrying trays are awful. I have stacks of the deep tubes because the trays have all cracked and are not stable. I think in most cases you don't need much more than a 12 inch deep pot if you can transplant it to the field soon enough.
What I have moved towards is really cheap tree pots from Amazon. They are supposed to be single use but I have gotten at least two seasons out of them. One thing that I don't like is that you can damage some roots when taking them from the pots. I think they are the best value for what you get though and work for what most here would be needing:
https://www.amazon.com/dp/B0BR9HZQ6Z?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1
I did have quite a bit of success this year with Zipset band pots. They are also cheap, stack densely into a container, but they are just a one-time use. Also, because they don't have bottoms the media you use is much more important:
https://www.greenhousemegastore.com/products/zipset-plant-bands
Band pots are what most university tree breeding programs are using. I think they last for several seasons and are easy to re-use, but I can't seem to find taller pots available for retail purchase:
https://stuewe.com/product/4-x-10-anderson-band/
Something I am excited to try next winter are Ellepots and airtrays. A few commercial tree nurseries I have been following have shifted over to start using these. They are combining the benefits of rootmakers with biodegradeable bags. I think they are likely overkill if you are just growing a few trees from seed, but if you like to try new techniques they might be worth checking out:
https://www.ellepot.com/ellepot-products/trays/ø120-mm-overview/006global/