JBL over kenwood for woofer anyday
RMS should be written on box, or manual,
another way to check the power of amp is to see the FUSE use on it, AB mosfets are abt 50% efficent, that means if ur amp has a 10AMP fuse, 10A x 14V=140watt MAX, divide by 2, 70 watt RMS.
For main speakers, u need abt 60-80watt RMS per channel, (all channel driven with least distortion at 4 ohms)
for Sub, u need atleast 200watt RMS,
cant comment on solid audio, depends on wt it outputs,