You said building in your post so instead of an ARF I have been using the 4* series of kits to teach students how to build there second plane. Before that I used the GP Super Sportster. These are a bit better as a second plane but the Sticks are another good choice. The Aeromaster is a bit more advanced and may not be a good choice for a second plane? If all you want to do is assemble an ARF then a good choice is the H-9 Pulse from Horizon. These planes are designed as a second plane and will be able to help you learn acrobatics but are much more stable. A lot depends on the pilots skill level when they move up to there next plane. There are a lot of good choices and if you do a search you will find a lot of threads asking the same question. Keep in mind therre is a lot of difference between building a plane and assembling an ARF. A kit built plane will take a lot more abuse and the second plane tends to take a beating.