I have flown most of the planes mentioned here and the 4* and the UCD 40 would be my two choices. The 4* is a good plane and flies well but to me its a antiquated and old looking design although its a good flyer. I personally prefer the more comtemporary 3D style planes like the UCD and Flip 3D if you are judging on looks.

However,
The UCD 40 size with a YS 63 is one of the sweetest and most enjoyable combinations I have flown. On low rates its is extremely docile and forgiving and it will glide in on landing approach better than any airplane I have flown and that includes 2M pattern planes, trainers. All of them. Only problem is that its a 3D type plane and although it is all but impossible to stall it doesnt like to fly in a straight line for long. If it has any forward motion at all, even the slightest bit it wont tip stall. IT tracks pretty well, but its not a pattern plane. Personally I think it blows the rest of them out of the water because of its docile flight and landing characteristics on low rates and potential to be a pretty solid 3D plane when you crank the throws up.

If you havent flown and landed a 40 size UCD on a calm day you havent lived. Its the most fun plane to touch and go I have ever flown.

Unless you have spent a little time with this plane you cant judge it, this is most definitely an excellent 2nd plane if not fundamentally the best there is for the performance you would expect out of a 2nd plane.

Mike