I have also never seen anyone getting PR with Canadian RA. My logic behind proceeding with application are:
1. Last year when CRS point requirement was high (>450) nobody with just RA experience nobody would get ITA, even if they qualify for FSW. RA experience just makes you eligible for FSW. It does not give you any point. Without work experience point it was not possible to get ITA before. Now, with points dropping we should see more and more people applying using RA experience.
2. In my work experience, I just put RA experience. I put my other 'less than one year' experience in personal details form. So, I am not misrepresenting anything. There system allowed me to be eligible.
3. I currently have NOC A category job. I am working there for 3 months now. Even if this does not fall through, I can apply again using CEC stream after one year experience. I am taking this risk to bring my spouse earlier in Canada. I have tried TRV for her before which they rejected. Now, I have two option, PR or SOWP. PR is safer option than SOWP.