It depends on what you are looking for. Daybreak has some strict rules about renting. So if it is for a rental, you will want to make sure you know the rules. Daybreak also has HOA fees. There a a lot of places in Herriman with no HOA fees. Daybreak is closer to SLC by about 10 minutes and has Trax stations. Both locations are starting to get more shopping and dining options but Daybreak is ahead of Herriman right now for amenities. Daybreak has a very controlled development philosophy so if you like their strategy you can count on keeping things the way you like them. Herriman is changing from a low density community to much more high density. Where Herriman goes from here is much less predictable, but likely to continue to be higher density developments from here on out. Daybreak has more community amenities like club houses and pools. Both have similar school options and community parks.
Honestly it depends on your goals. @Raquel Robertson has a lot of good points. I have clients that love daybreak and others that wouldn't touch it with a 10 foot pole. If it's a single family home the HOA fees are not terrible considering the amenities. Townhomes end up with 2 HOA. One for Daybreak and one for the Townhome development. Personally I would focus on the deal that I got over the specific city in the salt lake valley. Riverton, herriman, south jordan, West Jordan, bluffdale. I would be open to all of them and try to find the house and the deal you are looking for.