ES3 or G3B?

I have been DCA-ing in POSB IS G3B since 2015 and have recently increased my monthly amount to $500/mth with $4.10 transaction fees. I'm not sure if it makes more sense to change my strategy by DCA-ing quarterly and using DBS Vickers Cash Upfront at 0.12% commission charge. Any disadvantage by doing so? TIA.