You would be able to select the money changer closest to you or by rates. The exchange rates are updated so you would get close to the spot rate minus the MC’s take on the spread.
Not really/significant. It has been hovering between 3.03 and 3.08. I hv done some trades between Apr & Jul 2020 at over 3.07. Since then, RM has strengthened against S$ with me trading at 3.05 between Oct and Dec 2020. RM has just given up some of the climb it this year and back to the rate in Dec 2020.