I have owned a couple of the Midwest Little Stiks, a Sweet Stik, several Tiger Stiks and flew a friends Big Stik quite a bit and everyone was a fine flying plane. If you are wanting to buy a new engine then maybe the Big Stik is for you. If you want to use the engine from your trainer then the 40 size makes sense.

I like 25-40 sized planes for my own taste. A little easier to store and transport and easy on fuel. My first RC plane to build was a Little Stik with a 48" wingspan. Thats what I really learned to fly on. I flew and crashed the first one until it just wasn't repairable any more. So I built a second Little Stik. Same thing. I just flew the wings off it. Then I built the slightly larger Sweet Stik with a 54" wingspan and it was the best. I used to go by myself and just do touch and goes all day long. Wind didn't matter. Wind was a challenge. Most of my own designs were just modified Stiks with a cabin added. They were allthe plane I ever really needed.

I liked the Sweet Stik so much I just found the plans with a template sheet on Ebay. I bought a copy and I plan on scratching out a new one. I may make two while I'm at it. There are no bad choices when it comes to stiks.