I think the Mig-3's big claim to fame is that it was the first Mig fighter to serve in the Soviet Air Force. They fought early on in WWII but not in the same numbers as the Yak fighers.
I think the classic Russian WWII fighters are the Yak-7 and -9 series and Lavochkin La-5 and 7s. I believe the 'P-51' of the Soviet Air Force was the YaK-3.
Hobby Craft was great in the late 80's when they started coming out with various Russian WWII fighers in 1/48 before anyone else did. I think the jewel of Russian WWII aircraft kits the Accurate Miniatures IL-2M3 Sturmovik.