Hi,
I can't give you a definitive answer as I don't know all the variables, but if I had the same option (and with the benefit of hindsight, I know how many hours training it took for me (JAR license)) here's a breakdown of costs... By the way, I already had a multi CPL (about 10 hours twin time)
Option 1:
(19 hours training + 2 hours test + 9 hours PIC) * $420 + test fee $650 = $13,250
This gives you 30 hours twin time
Option 2:
(19 hours training + 2 hours test) * $600 + test fee $1200 = $13,800
This gives you 21 hours twin PLUS 35 hours = 56 hours.
Of course, I have no idea of the hour requirements under your legal system. I was on an integrated course, so I was flying frequently on instruments from about 20 hours. You need to take some realistic numbers for how much training you think you'll require and put that into the above equation. Then you'll be able to compare the two possible outcomes. With the numbers I've given you, I'd say option 2 is a no brainer.
But then, I don't know how many hours you'll need to pass the IR, nor do I know whether an IR will be of any use to you in your part of the world.
Hope that helps.