Here's a good skill/weapon layout to use: 1 reload, 1 bizman, 2 reload, 2 bizman, 1 med, 1 regen, 3 bizman, 3 reload, then whatever you want. Weapons should be: revolver, uzi, AK47, M16, Striker. You can buy the rest if you want (for achievement), but after the striker weapons aren't that good. It'll be hard to get the uzi without bizman, so get that in early.
For some reason, I find SCGMD3 more difficult to play than 2, and not just because of the extra hold key. Maybe the fact that there are four lines instead of 2 is what's getting me.
For those confused about mission 10: you have to shoot the box, then when the guard comes out, shoot him in the leg. The door will open and when it does, shoot the box inside; this will prevent the door from closing. Hope this helps.
I find that if I pay any attention at all to the bonuses, I instantly die. Therefore, my tactic is to get energy drinks/caffeine and drool while only having a slight idea of where the coaster is. Using that tactic, I managed to get to around 12,000 in distance.
Wish the highscore mode allowed you to unlock upgrades, but only per run, so old-timers wouldn't have much of an advantage. As you get to certain distances, you unlock new stuff.
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