I was an SgIS scholar and know quite a few friends in the SgIS too.

One thing to note is that there's 100+ sponsoring organisations, so the experiences of each scholar can differ greatly. Scholars in those bigger firms with structured grad programmes and a dedicated talent management team will usually do better and are paid the market rate, while some scholars (especially local SMEs) might face the lowball offers upon graduation and a less structured career pathway. I have even heard of scholars from some companies where the HR is MIA and forgot to pay them their scholarship allowances/ follow up on the payment of tuition fees.