I've been a longtime user of LaunchBar and Keyboard Maestro but heard a lot of great things about Alfred, including reading some reviews of people who ran both Alfred and LaunchBar. Alfred just came out with V3 so I decided to take the plunge and give it a go. Downloaded V3 and bought the PowerPack. Without the PowerPack the app is pretty neutered, and that's fine. I don't mind paying for quality apps. I made a serious attempt to use Alfred exclusively for a week in order to get familiar with it and give it a solid trial. I also created a few custom workflows and got sufficiently in-depth with it that I assisted a longtime Alfred user on the forums as we debugged a v2 workflow and got it working for v3. If I thought Alfred was better than LaunchBar I would've had no problem switching, I'm all about using the best tool for the job, but Alfred simply does not measure up. It's just an inferior tool for the job. Searching is slower, configuring custom searches more difficult, and search results are far less complete and robust than in LaunchBar. Functionality that is built in to LaunchBar requires custom workflows to be added on, and the bottom line with Alfred workflows is they can be buggy as hell and are easily broken as the core engine is updated. LaunchBar is just a faster, better tool than Alfred. If you have Alfred and like it, great, keep it. It's a nice app. But if you are looking for something like this and have yet to make a decision, do yourself a favor and give LaunchBar a demo trial.
I did like the Workflow functionality in Alfred, I think that's well done and pretty slick, but the few workflows I created I was pretty easily able to duplicate in Keyboard Maestro. The visual interface of Alfred for this is terrific, though.
one note: I do NOT work for LaunchBar. I've been a paying customer for many years now, I'm just well experienced in it.
One thing other than Workflows that I do like better with Alfred is they have a MUCH more active and robust user forum. The one for LaunchBar is basically dead. And I had to reach out to Alfred support about a conflict with a java app and they were great. The folks who develop LaunchBar are not great at providing support, frankly. It's a problem I wish they'd rectify. That said, just looking at the products, I'd conclude that both are high quality pieces of software but for the core launching and searching functionality, LaunchBar just does it better.