4 guitar songs I've had little or no trouble with:
Let it Be
Oye Como Va
Blackbird
Day Tripper
White Wedding
Life in the Fast Lane

3 guitar songs that give me trouble:
La Grange
Hard to Handle

4 guitar songs that will be a big challenge for me:
Crossfire
Voodoo Child
You Really Got Me
Any Lynrd Skynrd song


I'm not saying that these 4 guitar songs were a breeze, it's just I was able to get through them with little trouble. Looking at them, it's probably because they don't have extended solos or don't require much in the way of speed in the solos.

Why you may ask? In the case of La Grange, it's because it uses a technique (hybrid picking) that I haven't learned/mastered. Hard to Handle has some speed and combo of notes that just had my fingers tripping over eachother.

It was for this reason that I had made a suggestion that songs be indexed to included required skills to play them. It would take some of the subjectivity out of the difficulty rating.