Ouch, that would be very heavy for the Funtana s90.

The s90 was designed with a four stroke .90 in mind.

At best your 1.20 would be perfect for it while keeping it light.

The Funtana is NOT in any way built for speed. It is essential to keep the flight speed down or it will flutter and self destruct on you.

It is meant to be a slow but powerful 3D flyer.

I have no problems flying it with a Saito 1.00 using a 16x4W prop. This keeps things light and gives the Funtana good vertical pull.

Your 1.20 would do well.