SS's selling point is that they are like mini mart or mama shops. Their vegetables can be purchased by quantities, no need to buy in prepacked packs. Can also just buy 1 aussie potato, 3 cloves of garlic, 1/4 lotus root, 2 pcs of ladyfingers, etc

Customers can also handpick these vegetables as well.
They also sell uncommon brands which most supermarket do not sell eg. asian spices and condiments in mini packs, dried goods, rice, small tofu (which is sedap) and european salad dressings. The prepacked fresh salmon is fresher than NTUC. The only problem is their leafy vegetables do look sad so NTUC is the option. Some basic items are substantially cheaper than NTUC, CS, Giant and redmart (eg. rice, kitchen towels).
Cold storage is good for uk and european products and household cleaning ranges, but always need to check the expiry dates for all their products and quite a number of products are also expensive by min. 40 cents.
Non-vegs/fruuts and heavy/bulky items best buy from online retailers, eg. Redmart gives good discount and delivery is very punctual. Delivery during non peak period gives an extra $1 discount.
Honestbee best for buying refrigerated and chilled products as you can indicate the preferred expiration period for them. It also have delivery slots within a few hours.
Till now customers still have to buy from different sources. But i think Sheng Siong has its unique selling model which other supermarkets and online stores cant emulate for now.
I dont own SS stock though but i have a soft spot for sheng siong for the above reasons and the management treats their empolyees well from the articles and by word of mouth.