Ok im sure these types of questions are a dime a dozen but anyway. What would you think i would be more suited with, i need a power house for my 14lb warbird and im debating between these two engines.

OS FS Surpass II
Displacement: 0.702 cu in (11.5 cc)
Bore: 1.02 in (26 mm)
Stroke: 0.87 in (22 mm)
Practical rpm: 2,000-12,000
Output: 1.1 bhp @ 11,000 rpm
Weight: 20.3 oz (580 g)

or

OS 2 Stroke 91 FX
Displacement: 0.912 cu in (15.0cc)
Bore: 1.091 in (27.7mm)
Stroke: 0.976 in (24.8mm)
Practical RPM: 2,000-16,000
Output: 2.8 bhp (ps) @ 15,000 rpm
Weight: 19.3 oz (550g)

basically i want to be able to fly the plane scale but i dont want to have a problem with getting her up in the air and doing pretty decent stunts. Nothing like a sport plane just your normal stunts. So what would you suggest is the best way to go. I do like the fact that the Surpass is 4 stroke so it will give it that sound. Anyway, suggestions?