The 10X multiplier was actually the easiest one to get, took a lot less time than the others.
If you're looking to get studs, I'd recommend saving up your money for the 2X multiplier, I think it's only 1 million, maybe 2. On top of getting you more studs it makes getting True Jedi easier, which also counts towards overall game completion. I actually don't remember it being too hard getting to 1 million, even before I bought the multiplier, maybe three or four levels worth if you destroy everything. The first level in particular was pretty good since the walls were destructable and there was a 'big bounty hunter only' area.
Super story is just story mode but with all the missions tied together and 60 minute completion being the goal. This was actually the most annoying thing in the game, even moreso than getting the undefeated achievements for the vehicle levels, because you can't save and you can't skip the cut scenes so it's already an hour + commitment, and on top of that it's surprisingly tough to run through all the levels in 60 minutes. The kicker was than you can't enable any extras, so no invincibility and no fast build/fast force. The weird thing is that I remember having a bitch of a time trying to clear the ROTJ super story, and I took just a minute or two over an hour and I still got credit for it(It was the last thing I needed to get 100% completion and the achivement), so I'm not sure if the time limit is necessary.
For the Mos Eisley bonus mission, buy the invincivility cheat and play as a bounty hunter so you can user grenades and blow up the silver tanks, Greedo is supposed to be the best since he's the fastest. Just run around and ignore the enemies and concentrate on blowing up the tanks.
Basically, if you buy invincibility, fast force, the minikit detector and 2X multiplier , going back to collect minikits, studs and to achieve 'true jedi' will be a ton easier. You can't use any extras for undefeated achievements though, or the super story missions. Score multipliers won't work in the character bonus missions either but the others should.
BTW, if you get all 99 golden bricks you'll be able to build a oil well-type thing outside the cantina that shoots out infinite lego studs. That's how you're supposed get all the ridiculously expensive items like the more expensive multipliers and extras. After that it's easy, but ridiculously mindless(think 30 minutes of jumping around a free flowing spigot).
