It's one way to make the career switch but possibly not the best. As with most things, it depends on your circumstances.
What OMSCS offers imo is:
- an elite CS education
- specialize in topics that interest you
- very low cost (I'll have spent around $8k total by graudation)
- the flexibility that naturally comes with an online-first education
What it doesn't offer:
- a starting point for someone with near zero cs-background (if this is you, it will be a hard program)
- job/coop placement
- networking is hard imo