Some info...
20 shots per flight, in theory...
A shit load of chemical energy. You might want to ask about ozone layers and HCL emissions, but maybe the airframe won't survive for long enough for it to matter. :-)
And then there is the Iodine and multiply-ionozed Oxygen. Basically, stand WELL back and watch the fireworks.
But let's not be totally negative. If someone told me, cold, that a plan existed to mix liquid H2 and Liquid O2, in a controlled not-quite-explosive fashion to achieve LEO, I would have laughed...
I would also have been wrong.
So perhaps lasers have a present reality and a future purpose, but perthaps not, also