Hi marty and welcome to AFF. I assume you are talking about travelling from Sydney, Melbourne or Perth via Singapore to Bangkok.
Scoot, a subsidiary of Singapore Airlines, has a purpose and they transport people around with minimal frills, theoretically for fairly low cost.
I have travelled them a number of times and will do so again. Some of my opinions, and this is about the longer sector from Australia, not the shorter sector between Singapore and Bangkok :
1) Seats are fairly cramped, and unlike most carriers (even Jetstar) most seats do not have adjustable headrests. Fine if you're short, but if you're tall it's not just the legroom that is cramped, the seats seem fairly short and I miss the adjusting the height of the headrest.
2) Having said that, you can assign better seats (with slightly more legroom and adjustable headrests) for a fairly minimal fee. I do this, and makes a world of difference. Also, it is often not too expensive to pay up to ScootPlus, which is basically premium economy. You get luggage one meal/beverage included with ScootPlus, free seat power, a very small amount of Wifi and of course the bigger seat/better legroom.
3) You, in theory, are not allowed to bring your own food on board to eat. However, if you are tactful and eat it outside of meal services (when crew are actively coming through the cabin) and take your own rubbish to the bins for disposal, you're not going to be told off. I take sandwiches, cut fruit and snack, and never had any complaints. But don't take anything that reeks (such as tuna sandwiches or hot food). IMHO, the policy is both to encourage people to buy food on board and to discourage them from taking smelly curries, fish soups etc on board!
4) Unlike Jetstar, they do not even provide water. Take an empty refillable water bottle and fill it up once you have passed through security (as long as you don't mind drinking water that comes from drinking water fountains at the airport).
5) BYO entertainment.
6) If you need to cancel, you can only change to other dates for the exact same journey (you can't apply $$$ to a different sort of trip), and must pay change fee and any fare difference.
7) Very generous with carry on luggage (10kg) and rarely enforced, unlike Jetstar who only allow 7kg.
8) Short haul is like any short haul LCC, cramped, but you can purchase exit row.
Basically they're a bus in the sky, but are OK. I've had less cancellation and delays with them between MEL & SIN than I have with either Qantas or Jetstar.