G'day Mate,
I had a Giles 202, see pix.
I used an OS160FX, with a Bisson pitts muffler, 10% nitro, and swinging a 17x10 APC prop, a 16x10APC works well too.
Easy plane to fly, once balanced, would easily do knife edge circuits with no coupling, at 2/3 throttle, a joy to fly & land.
But make sure your balance point is not forward, ie, nose heavy. Start off at the recommended balance point, then move your batteries back after a few flights, & feel the difference.
And with the 160FX, no need for pumps or regulators, just sit the tank in it's normal position & fly the thing.
As you can see from the pic inside the fuse, the battery pack was under the wing tube, for the first flight then I moved it back progresively, until it flew properly.