You'll be just fine....
... A sub is never exactly 2ohm or 4ohm
Then the ohm changes do to conditions ( they rise )
... I was running a Hifonics Zeus 606 ( 600max x 2 - 300rms x 2 ) @ 1ohm stereo - Never cut off
( It did get overly warm - until I placed the amp in my port... and it's was operation temperture then )