"Dynamic" became a dirty word when it was abused by amp/receiver manfs.
What people look to now is the FTC power.
How much power can the amp provide long term, over what freq range, with what amount of distortion?
However, knowing the above, I think dynamic or peak power has some utility. Some amps might have bigger capacitor banks, providing more power for a longer period of time (like 2 seconds instead of .2 seconds).
Movie soundtracks have a lot of transient sounds that need more power for a brief period.
I'd guess your receiver provides 50w power (8ohm) for the front two speakers.