[quote name='gary mac' timestamp='1433769697' post='2793762']
I find some disco lines a challenge, not so much because of any complexity but more the tempo and the octavingness
[/quote]
For the same reason 'Uprising' by Muse.
One I have tried very hard to get right (and still struggle with by the end) is 'Keep The Faith', Bon Jovi. I play with a pick and have found making the fast changes between strings rather than just grazing down as a finger style player might just doesn't sound right. I sort of cheat and play it as a pull-off and hammer-on which is the only way I can get it to flow. But nailing the overall vibe of the bass line, nuances in how long the notes are held, getting it all to flow properly without derailing has been (continues to be?) a long process.