The answer is "it depends".
Clearly transferring into a PRSA (if that's possible - there are some complications around this) or a PRB means that it is independent from your new employer's scheme.
The real issue is what benefits are you getting in the new ? Is the salary similar to the old employment? How many years service will you have with the new employer? If you took a transfer into the new scheme, what credit (additional service) would you get?
Do you not have an option to take a deferred benefit in the current scheme (leave the benefits where they are)?
On the basis that the new employer scheme is also a DB scheme, you would need to find out what benefit the Transfer Value would buy. How many years service? Having accumulated 15 years with your old employer (based on your salary at date of leaving, but indexed going forward at CPI - max 4%), you would need to calculate whether the years of addidional service offered in the new scheme (based on an estimated salary at retirement) would likely exceed the pension accrued to date (but indexed going forward.
On the other hand if you went for the PRSA/PRB, you would need to estimate the likely value at retirement age (based on an assumed growth rate to retirement age) and then calculate whether that might provide better or worse benefits than the benefit earned to date.
Whoever said pensions were simple!
I suggest you get professional advice in order to make a reasonably informed decision.