OK honestly? I don't trust styrofoam for growing edible plants -- but I know many people use them, so that's up to you to research and decide.
Two issues -- 44 oz does seem a bit unnecessarily big but it's a drink cup right? -- more of an issue with the height if you are growing under lights (height of the container plus the plant height) and drink cups with narrower bottoms tend to fall over easily (plus styrofoam so very lightweight) so you need to think of a way to weigh down the soil (I used pumice gravel with 24-28 oz plastic beverage cups) and still had to hogtie the cups and the plants together. These plants quickly outgrew the available height under the lights and needed to be carried outside for the day and inside for the night.
If you decide to get and use them, you might consider completely cutting an inch or two off the BOTTOM of the cups, then packing some moist potting mix in the bottom and putting them on web trays and then transplanting. Once the tomato roots fill the bottom the soil and plant will not fall out. I could also picture jamming a piece of newsprint in the bottom of the cut off cup then filling with potting mix. The paper will break down and dissolve by the time the roots fill the bottom.
Learning never ends because we can share what we've learned. And in sharing our collective experiences, we gain deeper understanding of what we learned.