I never learnt scales, why? because every slash/songs solo is based on a scale and by learning the solo and the notes used your obviously learning that scale!! So for a song like "Its so Easy" Ive learned the song note for note till the 2nd solo. Its not a very interesting solo and doesnt stand out much so i didnt learn it. Instead i re-used the notes from the first solo to play along with to the 2nd. So when i get in a band and hopefully we cover it i'll just do something sponteanous! Not to say am going to play something different everytime, i always fall into the same sort riff/hook.
This is far more important than learning noodled solos and outos, its understanding "what sounds good" what fits! So for solos like November Rain outro, instead of learning a solo comprised of a massive combinaiton of frets 15, 16, 18 on the first string, 15, 17, 18 on the 2nd etc, just remember the notes/frets used and follow the flow of the song!! so when it comes to improvising you know exactly what songs right!!
Later Axl