If you're changing terminals and going from the end of one terminal to the end of a different terminal (which is possible even when connecting SQ to SQ), then Changi is a nightmare. The trains are pathetic and only take you part of the way. You still have to do LOTS and LOTS of walking, which takes time and is exhausting. I went through SIN in February, and in both directions I had a horrendous amount of walking to do and hated it. Honestly I prefer an airport like DFW (a US airport!!!) over Changi, because the trains will whisk you anywhere in minutes.

For this and other reasons, I find Changi overrated and have never understood why so many people like it.

But to get back to your question, I would never accept a 1 hour connection at SIN if I were in your situation. But to each their own.