That story went on to see good triumph over evil...and also saw the Grandmaster abandon his creations. The team later appeared in DEFENDERS #13 and fought that new team, but Nighthawk decided to become a hero and joined up with them. Doctor Spectrum fought Iron Man a few times and became separated from the Power Prism which has bonded with a variety of characters since. Hyperion then died in battle on Earth-712 at the hands of his counterpart and Whizzer continued his life of crime under the new name Speed Demon.
So...if that's the Squadron Sinister, what's with the Squadron Supreme? Excellent question! That particular hero team debuted in 1971's AVENGERS #85-86 by Roy Thomas, John Buscema, and Frank Giacoia.
In that tale, Scarlet Witch, Vision, Quicksilver, and Goliath (still Barton) wound up on Earth-712, the home of a team much like their own made up of Nighthawk, Dr. Spectrum, Hyperion, Whizzer, Lady Lark, Tom Thumb, American Eagle, and Hawkeye.
Though the Earth-616ers foresaw a devastating event in that parallel Earth's near future, their presence at Squadron Supreme headquarters—located in the same relative location as Avengers Mansion—led to a big fight. After receiving word from Spectrum about a launch, the Avengers put two and two together and realized that the ship would cause the destruction they witnessed in the future.