Those speakers could handle more power than the 800 watts amp. Which is good, because it wont have enough power to blow them up.
800 watt is pretty plenty.
Just make sure power rating is with in same values. Its better to have an underpower amp, rather than overpowered, but even with a powerfull amp, you can control the output with the gain control.
Depending on your set up, There are other features that you might want to consider before getting an amp. Bridgeable, high-mid-low pass, etc. etc.