I think that you absolutely should give the game a try. It's a blast. I'd say to start as a player first, if possible, before trying to GM, but either way, I think it would be really eye opening. I know that it was for me.
Some of the concepts are really odd-seeming coming to that game from a predominantly D&D playing group. My players had to kind of adjust to the player driven nature of selecting scores and to some of the other elements. Here's a few.
Stress is a resource that each PC has. They can "take Stress" to use certain abilities, or to push themselves to increase their chances for success or the results when they do succeed. They also can take Stress to avoid negative consequences of one of their actions. So if the GM decides that a poor roll on their part results in an enemy harming them, they can override that Gm decision and reduce the amount of harm they take by Resisting the Consequence, which potentially has a Stress cost. The amount of Stress you can take is finite, and when you take your 9th point of Stress, you're out of the score (knocked out, left for dead, otherwise removed from action depending on the fiction) and you also develop a Trauma, which is an ongoing mark of some kind from your ordeal. It's a really powerful way for the players to influence the fiction. I think my players found it odd at first, and kind of mistook Stress for the game's equivalent of Hit Points, which it kind of is to an extent, but once we played and they saw it in action, they grasped it pretty quickly. I mean, it's a resource to be used when needed much like many elements of D&D, so it's familiar in that sense.
Another element is the way gear is handled. At the start of a Score, each player declares the size of the load they will be bringing: light, normal, or heavy. The size of the load you choose to carry indicates how conspicuous you are and can impact certain actions you take that may require speed or stealth. Each load size grants you a certain number of inventory slots and each character has a list of possible items they can have, and that list indicates how many inventory slots each item takes up. You don't need to select what items you have until you actually decide that you need to use the item. So if the crew is infiltrating a rival gang's base, and they find themselves needing to climb a 25 foot wall, one of the characters can mark off "Burglary Gear" which lets them have a rope. Nice and simple.
Flashbacks took a lot more adjustment, but they work in a similar way to Load/Gear. When they were getting ready for a Score, the players would start discussing details and plans, and for the first few sessions, I let this happen. But I started giving them less time to prepare and discuss how to go about the Score, because the game wants you to get to the action, and then work out the plan as you play. Very much like how a heist movie will alternate between scenes of the crooks on the job with scenes that show how they prepared, the game allows you to Flashback to earlier and take actions in the past that help deal with how you face the challenges during the Score. The idea here is that your PCs are capable and would prepare and plan accordingly, but the game doesn't want to spend time with players staring at a map and talking about entry points, and endlessly debating variables. So this allows you to avoid that, and then focus your prep retroactively depending on what actually comes up.
There are more elements to the game that really put things in the players' hands, but these are the big three off the top of my head. My players found each one to be different than what they're used to as players, but as they got used to them, I think they've found them really interesting. The design of the game and the theme are deftly woven, as [MENTION=16814]Ovinomancer[/MENTION] mentions above, and I think seeing how the desired experience is supported by the game's design is also really enlightening.
I can't recommend the game enough, just for the fun of it. It's really enjoyable and my D&D players are really digging it. In addition, I think it would also add to these discussions we have online; I think one of the main reasons these talks devolve the way they do is because some folks are talking about all games, and others are talking only about one specific game. I think if you see some of these mechanics in play, you'll better appreciate some of the points others have brought up.