Game was enjoyable until the pay-walling got in the way. Which was basically after a couple of levels. It's such a shame when games like these have so much potential yet are ruined by making it clear that if you want to progress at a decent speed, you gotta pay money. Sure maybe have the option to pay-to-win, just don't shove it in our faces every time we go to the store screen.
To get 6000, have everything upgraded, get your resistance as low as possible while flying. While flying, once you get down to 175MPH, use rockets to get to 200MPH and repeat. Angle upwards slightly if your altitude becomes to low.
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