If my monthly electricity consumption is around $50 (based on past bills), is it worth it to switch to open electricity markets?

It's always better to switch cause the rates will be cheaper. Just go and sign up on the retailer web site. Many find the options from all the retailers too confusing and swamped by it. If you are not so sure, choose a lowest fixed rate plan for one year to test water. Before you do so, there are few things to prepare.
1) get your latest SP bill ready.
2) check switching retailer discount.
3) check you get referrer code.
4) determine how you want to pay the bill, GIRO bank account or credit card (most have rebate).

The average cash back from switching is about $30 and monthly saving from lower tariff is about 23%. Hope you find this info useful.

I did an in-depth study and analysis on the situation and here are my findings: Open Electricity Market in Singapore

Thereupon, it will give you a better idea on each types of plan and whether it is suitable for your needs in the next few years (depending on the length of your contract). Given that this is a legally binding contract, the retailer will not be able to alter the price during the contractual period (subject to relevant terms and conditions as stated in the contract).

In the end, I went with Ohm Energy as I was impressed by their level of customer service. While it may not be the cheapest, I prefer to have a peace of mind with my choice. You may read about my thoughts here: Ohm Energy Review: I am Impressed

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