Phased Shields Question

[Power Man]

I have tried looking this up and can't seem to find an answer.

I just got Phased shields level 1. They produce 70 Phased shield points per unit.
My Question is are these better than the regular Shield level that produce 300 shield points??

I know that the phased polaron beam goes through regular shields. But how does the Phased shield work against regular beams??
My enemies do not have the Phased Polaron beam. Should I keep the regular shields at 300 points or retrofit (yet again) my ships to have the Phased Shield at 70 points??

I will keep studing shields but I have a few other things to work on first.

Thanks in advance for any answers.
Happy Holidays !!