John
As you may know I am a Battery 3 user for awhile now. I just did a song using BFD 2 and I am impressed.
Battery 3 is still a very useful drum machine but BFD 2 is the way to go if your needs are not as eclectic as mine are. Having both is the ideal situation.
One neat thing that is a bonus is BFD2 shows up in the PRV with the drum names without the need of a drum map. DR008 did that too. Battery 3 doesn't.
I'm a huge BFD2 fan. It's just a fantastic plugin, offers great flexibility, has great effects, is expandable, works great in Sonar. What's not to like?
In addition, Platinum Samples has the best expansions for BFD2 (IMO), with some of the best drum sounds I've ever heard in the Joe Barressi and Jim Scott packs, and if you're more of a classic rock guy, there's always the Andy John's pack too, which also sounds great. They also have a ton of grooves in different genres.
Disclosure: I test for both companies, but in both cases, I was a customer first and later became a tester. If I didn't strongly believe that these are just fantastic products, I'd just keep my mouth shut and not post at all.