S&P raised the ratings on five classes of notes issued by Q10 Trust, a securitiser of subprime and non-conforming mortgages. Ratings on the Class B, C, D, E and F notes were raised to 'AAA', 'AA+', 'A' 'BBB' and 'BB' from 'AA' 'A+', 'BBB+' 'BB' and 'B', respectively. The 'AAA' ratings on the Class A-2 notes were affirmed.Amortisation of the underlying portfolio to less than 16 per cent of the original A$1 billion of mortgages means the notes are now adequately supported to withstand stresses that are commensurate with the higher rating levels.  Approximately A$17 million of excess spread, after covering prior portfolio losses, has been accumulated in a reserve to absorb future losses. To date, there have been no charge-offs to any notes, which would not occur until the A$17 million uncapped reserve is depleted. While arrears are high due to adverse selection at the tail-end of the transaction, the transaction has adequate credit enhancements for the rated notes and minimal negative portfolio-yield risk at the tail-end.S&P affirmed the ratings on all classes of subprime and nonconforming RMBS issued by Pepper Residential Securities Trust No. 5. The rating affirmations reflect its view that the rated notes are adequately supported to withstand stresses that are commensurate with the current rating levels. Although the credit enhancements as a percentage of the outstanding balance have built up as the portfolio amortized, in S&P's opinion, the current portfolio composition remains susceptible to adverse selection risk, and the pro-rata pay-down of the notes may limit further build-up of credit support to the rated notes.