I've seen this question in this context brought up a few times and IMO it depends on what the SID says and when you are given the heading.
SID 101 - all a SID is is a shorthand for a departure clearance to reduce workload (both the controller's and yours). It's a set of ATC instructions and like other ATC clearances and instructions, can be superseded by new instructions. With that in mind...
In this case for a 23L departure, the SID says:
Climb on runway heading 227° until I-FVJ 2.3 DME and 1200 feet or above, then fly assigned heading 210°, 227° or 242°
Who is giving you the heading you are talking about? And exactly what are they saying?
If it's from the tower on takeoff, I'd say it's the "assigned heading" that you fly
after reaching 1200/2.3 D.
OTOH, if you are contacting departure and the controller says, "radar contact. Fly heading XXX°," it's a current instruction that overrides the SID heading.