Test 3g speed bro
It's like my speed is very intermittent. Most of the times sloe, have to reset my data then it gets better for awhile
I've seen the same on most recent phones I've tried on singtel 3G. Speeds are in the same ballpark too. And data drops once in a while and require a toggle of airplane mode on and off to get it working again. Tested on Redmi, Redmi Note, US set 2013 Moto X, US set Moto G, local dual sim 2013 Moto G, Motorola Razr i, Nexus 4, Galaxy S3, and probably a few more 3G only phones that forgot about.
Not to mention I've noticed poorer reception too on 3G only (or maybe because it's slow i think it's poor, who knows). Maybe its just Singtel allocating more bandwidth to LTE users? Cause I have great experiences on LTE speeds with Singtel, stable and decent speeds, and good reception too.
Anyway, with newer phone these days, I don't think having 4G on consume that much more battery life. The modem are generally more power efficient in my experience. If your speed is fast, things loads fast, you get things done fast also. If change to 3G, things loads slower, things get done slower. You need to leave the screen on longer, and screen is always the majority part of battery use if you always check the battery usage stats. So end up maybe won't save that much also. 0.2 cents here.