a bit irrelevant to this thread (Singlife) but can shed light on why multiplier is best?
are you just assuming one will hit income/dividend + 3 categories and has $100k AND has a monthly turnover of $30k or more with the bank?
cos if it's just income/dividend + 1/2 categories, the interest is only for $25k/$50k, while the other banks earn up to $70k/$75k with seemingly marginally lower rates, say 1.8% vs. 1.2% (compute it in absolute dollars, the interest might not differ much). and unless one has products already with DBS (e.g. home loans, insurance, RSP, etc.) one actually has to spend on their products to get those extra interest dollars. not sure if it's worth it actually..
for those with larger capital like $100k, $150k it might make more sense to spread out using the other banks to park their excess cash?