You are advised to use future funds transfer or future bill payment if the amount fluctuates all the time. However, if the amount is fixed or doesn't change frequently, eSI is more convenient for you.
Yes, you can place eSI for interbank funds transfers to participating financial institutions. The bank fees for eSI interbank funds transfers are RM2 for each eSI transaction, plus RM2 for interbank funds transfer (i.e. total RM4).
There is no limit for periodical funds transfers to own account(s) and payments to selected payee corporations. For periodical funds transfers to 3rd party account(s), the daily accumulated amount must not exceed RM3,000.