I don't know about the Seagull 300S, but I do have a couple of suggestions. One is the Goldberg Extra, never heard of one that didn't fly good. Best with a 120, though.

My personal favorite is the Vector Flight Extra, either the big one or the little one. A 60 would probably fly the smaller one just fine, mine flew great with an 80 fourstroke. I also have the larger VF Extra, and it's a dreamboat, with an ST 90.

Now, if you want another 46 size plane, the Sig SE or the Hobbico Super Sportster are fine choices.

Just my 2¢ worth,
Dave Olson