I still find myself flying the Sturdy Bird when I need to put a smile on my face.
I finally mastered the dratted thing, not that it flew all that well.
And there you have it. Opinions from opposite ends of the spectrum.
I doubt that
anyone will ever convince
everyone of any plane being the best, but I'll toss my vote to the Sig LT-40. The Sig Kadet Senior has probably taught more people than enything else, but it's out of date now.
And for the record, I learned on a Great Planes PT-40. Also a very good trainer.

Dennis-