If you wish to limit the premium to EUR 960 per year, then it is best to choose the existing system with the tax reduction of 30% on the premium contributed annually.
If you want to pay a higher premium than EUR 960, then an amount of up to EUR 1,230 may be paid with a tax reduction of 25%.
However, from a tax point of view, it is not attractive to pay less than EUR 1,152. A small numerical example (see table) shows that it is only from a contribution of EUR 1,152 in the new system that your tax benefit becomes at least equal to that of pension contribution of EUR 960.
As a consequence, it is advisable to make a contribution of at least EUR 1,152 per year if opting for the new system, since only then is the tax benefit equal to that of the existing system. However, it must be said that the additional tax benefit above EUR 1,152 is very limited in relation to the considerable premium increase.
It could be worth considering limiting oneself to an individual pension savings contract in the amount of EUR 960 and, additionally, taking out long-term savings policy that gives an entitlement to a tax reduction of 30%.