I have not only tried but acquired all of them actually (Classic, 2020, SE and LE) - yes, I guess that I am a little bit crazy
I must say that I do not really agree with audio123's review (quoted by ehjie): while the 2020 definitely has some specific qualities that the Classic has not (sonically: the mids, and of course the smaller shelf, that most people tend to prefer), I would not say that the 2020 are technically "better" than the Classic (as audio123 implies).
Whether one would say that the Classic / SE / LE are "better" than the 2020 or that the 2020 are "better" than the Classic / SE / LE is really a matter of personal preference, and it should be noted that there is definitely no "big" sound difference between all the Solaris models - they are really all in the same ballpark, with each having its own little specificities that make them just a little bit different.
Personally, I would say that I prefer the LE over the 2020 (although I still use the 2020 from time to time, especially when travelling), but I totally understand how other people can actually prefer the 2020 over the Classic / SE / LE.
At the end of the day, when comparing the 2020 and the LE (or the 2020 and any other Solaris really), I would say that the most important thing to consider (over the slight differences in sound) is really the size of the shelves.
It took some time for me to get used to the Classic's big shelves (in the first weeks I could not really use them for more than 1 hour straight), but somehow I did get used to them, and now I am able to use them for several hours without any fatigue (other than the "normal" fatigue that you can have depending on the style of music and on the type / quality of recording / mixing, of course).
So:
- if you do not mind the big shelves, I would say that you should maybe go with the LE (as they are a limited edition that is still available and as they are maybe a little bit closer to what I would call the "classic" Solaris sound than the 2020 - although, again, that's really a matter of personnal preference),
- and if you do mind the big shelves (or really prefer the smaller size of the 2020 and / or its sound, if you have the possibility to compare them), than you should definitely go with the 2020, which are great IEMs that are definitely in the same ballpark / at the same level of quality as the other Solaris models...
Hope this helps!