If your usual Singapore monthly groceries is about S$500/month
JB probably can help you save 30-40% of that == S$150-200 /month
You can add in how often u massage, eat at restaurants etc as well and the savings from it.
(we normally do not go massage every day, eat DTF every meal...)
You can spread it over a few trips or a few people if you are worried about GST allowance.
Just calculate and think per trip, how many hours was spent in and out vs time spent in singapore to get the same stuff.
Ask yourself whether is your time worth the trip(s).
If no, then don't waste time to go in and spend the time on other worthwhile activities that u normally don't get to do.
If yes, then you are most probably not of edmw level
