Scoot Magee confirmed is about +5, i don't have a way to record 60fps videos, but if someone is able to record by setting the AI do do 214 ex FB and jump after blocking the fireball and upload the 60fps vid on youtube, i will be able to tell exactly how much the block stun of ex FB is on block.
But after seen the video its definitely +8 due you being able to land a 7F hit before the AI being able to reversal the blockstun with backdash