That’s what I use and I feel like it’s been a very good return on investment, it makes my life easier, customer’s have commented on it and I’ve even seen some higher quality restaurants treat me a bit more professionally with it.
Edit: Actually, I got the six cup version and I’ve yet to see a cup that doesn’t fit in it, including trenta drinks and venti frappuccinos with the dome lids from Starbucks. Those are the only drinks I’ve unzipped the compression zipper to make it taller for as well.
I’ve never actually needed the six cups before but I have pulled one half out of it and put pastries or breakfast sandwiches in with hot coffees in the other half. It doesn’t look like the extendible height option comes with the four cup version either.