Guild Wars 2

Is there really a big difference between the following runes?

Superior rune of the pirate
Superior rune of scavenging

Does magic find actually help increase the drops of rare items?
I noticed on the Scavenging runes, it also says something about better rare drops.

Magic Find increases the frequency for magic gear drops. Magic gear is blue, green, rare, and exotic. It doesn’t give you more rares than usual per any given amount of magic items found, it just increases the number of times you roll for them. You’re gonna get a lot of blue/green vendor crap.

about the runes, there shouldn’t be any difference between the two besides the amount of the bonus it gives. 10% is better than 5% etc. It all stacks up to a total MF bonus.

Scavenging gives a total, if you’re wearing all six, of 35% MF.
Pirate gives a total, if you’re wearing all six, of 50% MF.

Magic find does in fact increase the drop rate of rare items. Say the rare has a drop rate of 1.5% and you have no MF except those runes.

Scavenging skews the drop table by a multiplier of 1.35. 1.5% * 1.35 = 2.025% chance of your item dropping.
Pirate skews the drop table by a multiplier of 1.5. 1.5 * 1.5% = 2.25% chance of your item dropping.
So, you are 0.225% more likely to see the rare you want, with Pirate, as opposed to Scavenging.