The instrument you pick changes the risk on both sides. A SAFE keeps things simple: no interest to track and no maturity date to miss, so nothing forces a conversion or a repayment if the next round is slow to arrive. That simplicity is why the SAFE has spread through Singapore's seed stage. The trade-off is that a pure SAFE gives the investor no scheduled way to recover the money if the company simply drifts.
A convertible note answers that by being debt. It accrues interest, usually at a modest simple rate, and carries a maturity date. If no qualifying round happens before that date, the investor can demand repayment or convert on the spot, which is real leverage a SAFE lacks. The note also ranks ahead of shareholders on a winding up, a meaningful difference if the company fails. Lending to a company also sits near the Moneylenders Act 2008, but that Act excludes anyone who lends only to corporations, so a convertible note into a Singapore company stays outside its licensing regime.
Between the two, the valuation cap and the discount behave identically, so the negotiation turns on interest, maturity and the downside. A founder confident of raising soon leans toward the SAFE; an investor who wants a floor leans toward the note. This document writes either cleanly, so you can send the same offer both ways.