Prodiamine. It does work against dandelion, although they're not specifically listed.

Dimension does list dandelion and works well too. Coverage is shorter term but can be reapplied.

Neither is perfect, you'll get 80 to 90% suppression depending on a ton of factors. Using Prodiamine, I get one or two dandelion a year in both the lawn and gardens, total.

Keep in mind that pre-emergents only kills germinating seeds.

The dandelions that you may see this year germinated last Summer and already has a large taproot ready to go this Spring.

Morph, I think I've asked this before without much luck but figured I'd give it another shot... Any thoughts on Snapshot? Great reviews on Amazon and protects against more than 3x the amount of weeds as Barricade.

Snapshot is an expensive specialty pre-emergent for ornamental beds, but more often (and intended) for growers of container and field-grown plants. It is not registered for lawn use.

What Andy said. I've never used Snapshot. It's too expensive, and Prodiamine works well in the gardens as well as the lawn (and doesn't impact any of the dozen species I use in the gardens).

Prodiamine/Barricade doesn't do much, if anything, against nutsedge in the gardens. Fortunately, Tenacity does.