Is the Mass Effect 2 DLC worth buying?

Kasumi and Overlord are ok. if you're in the mood to spend money, they're fun for a couple of times.

Shadow Broker, on the other hand... You have to buy it. Period. It's good if you've only played ME2 - good combat, lots of upgrades, excellent plot. But if you romanced Liara in ME1 (and want to continue that), it's nothing short of a roller coaster ride.

I only have the Kasumi DLC so that's all I can really comment on.

It's pretty fun, it gives you access to a new planet for the mission and Kasumi herself is fairly useful. She can't talk though. I mean she talks the same way Zaeed does, there's no conversation wheel or anything on the ship. But if you can deal with that, definitely get it imo.

Cerberus community would not furnish any gameplay on its own. it is quite, an in-activity get carry of device that delivers a spread of free downloads instantly from Bioware. the quite a few downloads comprise Zaheed (the mercenary that joins your crew, and also you are able to help with a project dealing with the Blue solar mercs), and new armors and guns.

i'd wait for the collection edition where all dlc is included