Advantages/Disadvantages PRSI S class

Hi. New poster to this site and just looking for general advice on the above.

My partner and two members of his family went out on their own some years ago. A limited company was set up, and they are currently proprietary directors, paying S1 PRSI.

My question is, (and excuse my naivity/ignorance on the subject), what are the advantages of paying S Class, aside from paying a lower rate of PRSI? The disadvantages are fairly clear - in the event that the company doesn't survive the current climate, my partner and his family members would not be entitled to any JB/JA, but aside from that they are not currently entitled to any Dental or Optical benefits.

Could they, as directors or owners of the company, have been paying a full Class A all along? Or once you set up in business, does that mean you must pay a lower rate of PRSI?

Sorry if this is long-winded and hopefully someone can clarify this for me.

Proprietory directors must pay Class S, it is not optional to pay Class A. The main benefits are State Pension and Maternity Benefit. Remember the employee Class S contribution is not much less than the employee Class A contribution. It is the employer Class A contribution which gives rise to the other benefits, JSB etc. and that costs up to 10.75% for the employer.

The only advantage to s class is that the employers contribution is lower. Alot of s class payee's do not know how rubbish it is until too late. I am sure most would pay the extra to have better entitilements or else pay none at all as there seems to be little or no advantage to paying it. You can not claim it back if you are out of work, no matter how much has been paid. Supposedly you are entitled to things like maternity benefit, but rather then having to work the usual 28 weeks in the previous year or whatever it is for A class, you have to work 52 for s class!! So not even time off for Christmas is allowed under s class. May as well say you are not entitled.
Basically, you pay less prsi, but get no advantage for having paid it.