I've been using Dimension for years and have mixed feelings about it. First off, forget about any post-emergent control unless you want to apply it nice and heavy, which you won't be doing at most recommended rates (esp split apps). I've always applied split apps about 2 months apart. On lawns with a history of crabgrass, don't expect complete control in the first year. Otherwise, it's on par with most any other pre-m out there. I've also experimented with Barricade and overall would say I prefer Dimension overall. At least the pesticide inspector leaves me alone when I'm applying it....since it's colorless, he thinks it's straight fert.