Mine has been trial and error.....almost all of my Tak LE's have been purchased new......although not a wide AFOV they are nice and sharp.
My favourite has been the Tak LE50 although a low power EP it throws up this beautiful sharp bright view.....it gets used a lot across all my scopes. In the Mewlon 300 a full moon fill up the entire field with just a very tiny gap around the circumference and is a beautiful sharp image.
Tak LE30 is great for planetary......as are the other smaller LE's.
My next Favourites are Nagler 31, Nagler 22 and Nagler 17 for their wide AFOV on clusters and nebulas.
I have just taken delivery of the new Tak LE40 which after initial quick test views shows similar promise to the LE50
I can't ever see my self selling the Tak LE50, LE30 or the Naglers
I occasionally use my Delos' which are a nice alternative to the LE's
I have a Pentax XW10 and Masuyama 20 (original) that never get used which I occasionally think of selling off ......however I tend to hoard so they sit there for DR/Redundancy reasons