I'm not sure what the .25LA weights, but to hang a .40 or .46 on there, you will come out nose heavy.
I have the OS.40FP on my banshee, and I was told to cut off 1.5" from the nose, which I did. And the CG came out just about right.
Alternately, you could-
Extend the fuselage aft of the wing,
Move the wing forward in the fuse,
Make a larger horizontal, which will weigh more.
If I was doing this again, I think I would opt for a wing shift forward, and make a slightly larger built up tail. It would be kind of cool to have a 30-34 oz Banshee.
I believe mine weighs 38 with not much attention in building, covered in MonoCote.
Good luck!
R,
Chris