I'm a fan of stroker builds because of how it broadens the power curve. Both mods make power in a different place. The big bore will pick up 2-3 hp from the midrange up. I've seen a stroker do 6-8 hp and 8 ft-lbs, but it is earlier in the powerband to the point that it doesn't affect peak power that much. The +5 crank is running around all over the place with big bore 14:1 pistons, and of course the Barker cranks are pretty much the standard by which others are judged. The stroker is more bang for the buck no matter how you slice it...... If you can install it yourself, it's a REAL bargain when you already have a good piston for your stock bore.
The cool thing about the stroker build is the torque on the very bottom if your build pulls double duty as a racer/trail machine. Less shifting and less fatigue. The wider powerband works well in racing because of the wide RPM gap between gears. It just takes a good rider to get the proper traction balance on launch. Another good thing about the stroker is that you can build the power of a high compression race motor in a more tractable package and it doesn't take long to pay for either a big bore or a stroker with the price of race gas vs pump. I personally believe that you will want both in the long run.
One thing you wanna do is find an engine builder that understands what to do with cam ICL, LSA, port volume etc.... to take advantage of either mod. They are
extremely rare
