Personally, the only advantage I currently see to using Blitz3D SDK over Blitz3D, is that the SDK will more than likely be supported for a lot longer than BB3D will.
That said, I don't think there's anything massively wrong with BB3D as it is.
As for Blitzmax's learning curve, the biggest things I had trouble getting used to, were automatic garbage collection (I didn't trust it at first!), and manual typelist management (which now, I couldn't live without).
The rest is largely the same, albeit object-oriented. But you don't have to go down the OO route if you don't want to.
That said, I don't think there's anything massively wrong with BB3D as it is.
As for Blitzmax's learning curve, the biggest things I had trouble getting used to, were automatic garbage collection (I didn't trust it at first!), and manual typelist management (which now, I couldn't live without).
The rest is largely the same, albeit object-oriented. But you don't have to go down the OO route if you don't want to.