Way more than I need! They work really well, but you have to be careful with the watering. It's easy to soak them or get them too dry, especially if you use a heat source under them.
Right now I've got a 72-pod tray going that's setting on a heating pad on medium heat. Once the seeds sprout and get some leaves, they get placed underneath a grow light (my first year to use it, so we'll see how that goes). So far, so good--you can see my results after about 10 days:
These are soggy because I had just watered them, but they dry out pretty quickly.
These squash plants are doing really well. I would also warn you that if you plant something like squash or morning glories that grow a lot of roots really fast, you should take the netting off the pods before they get very big. After a week the squash roots had grown through it, and I had a hard time getting it off without breaking the roots.
For tomato seeds, I didn't put them on any kind of heat this year, and they are coming up--it just takes a little longer. I still have some time before I can plant them, so slow is good.
You should either leave the top completely off the base of set it to where it gets good airflow--the pods may get moldy if you don't. A small fan works great to keep the air moving.
Good luck!