I flew this route yesterday, SIN-MNL. The machine was one of those with (more) flatter seats, 2-2-2.
I was going to post and ask why people rag on SQ regional J because it was really quite good....but then I flew BKK-SIN this evening on an older config machine, 2-3-2.
All the same, it's still reasonable. If you're complaining about SQ J of any kind, you need a good dose of DL domestic F to recalibrate your expectations @:-)