I prep all my meals and switched to these as I didn't want to keep heating things in plastic and they work great! The lids have a very good seal

I purchased a first batch of these glass containers in January as I meal prep my food each week (and take my lunch to work) and was in need of some new food storage containers of the SAME size (I didn't need a variety pack). I also wanted to avoid microwaving my meals in plastic for a variety of reasons. I liked them so much I bought a 2nd batch and now have 16 of them for my weekly food prep.

[There is a growing body of scientific evidence that is showing that exposure to plastics over a long period of time may be harmful. Plastics release chemicals into our food, and more so when heated. What constitutes as toxic or harmful is inconclusive; however, while there is obviously no scientific consensus that "MICROWAVING PLASTIC = CANCER," it's my personal OPINION that food exposure to plastic (esp when microwaving) would likely lead to some sort of measurable ill-effect, even if it's 50 years down the road. We already know that BPA and Phthalates are endocrine disruptors.]

I was pleasantly surprised. These containers are fantastic.

Pros:
-It's glass, so the likelyhood of any kind of toxicity is almost 0. In my opinion, while more expensive than plastic, it's a better option for your health.
-Price: these are very well priced for a set of 8 containers
-Because it's a truly non-porous material, it doesn't retain smells of previously held foods
-Glass is easier to clean than plastic.
-Because it's borosilicate glass, it's safe to put in the freezer or oven (lid is not oven safe). Also, when putting into the freezer, the container is air-tight, so no additional moisture/ice is getting into your food.
-It's leak-proof, so you can carry your soup around worry-free. Additionally, the lid is more secure than even traditional plastic containers due to the 4 locking tabs.
-The silicon seal is removable from the plastic lid, so you can take it out, clean it, and put it back in.
-Durability: Assuming it doesn't chip or break, borosilicate can last for decades. Plastic containers usually get stinky, deform in dishwasher from heat, etc after a few years. I've gone through many sets of plastic food containers.
-They are still stackable for storage; I store the glass containers on top of each other, and then lids stacked, as well.
-Everyone's needs vary, but this was pretty much the perfect size for me for my meal sizes. I'm glad I didn't go any smaller than the 30 oz, and any bigger I would have wasted space. However, they also offer a set of (5) 36 oz containers if you need a bigger size or tend to have meals with more volume.

Cons:
-Compared to other glass containers, none that I'm aware of, though these are my only set. I feel like these are pretty great quality and haven't had any issues to date other than a minor chip on the bottom part of one of the lids (hasn't affected seal since it's on the bottom, not top).
-While they are stackable, they don't nest into each other like other plastic containers: they nest within the inner lip of the top of the container. As a result they do take up more space than plastic containers when not in use.
-Compared to plastic, it's obviously easier to break.

Overall, these have been a great product at a good price, well made, and a superior alternative to plastic containers.

We are using these for food storage. The only issue is the material used to actually seal the container shut keeps coming out of its track when I open the container. It is easily put
back into place. Otherwise these are heavy-duty, quality containers.

I have a problem getting the sides to stay locked.

I like how well these are made. I threw out all of my plastic containers due to cancer causing agents when in the microwave, and have never regretted it. The lids can we washed in the top of the dishwasher and the glass to the bottom portion is very thick. I have dropped them a few times and they are perfectly fine. I Highly recommend this product.