Intro: The right construction approach depends on what a facility actually needs to do over its operational life, not on which option sounds more impressive. A few honest questions do more work than a general preference either way.
How Often Will Training Scenarios Change?
A facility that will run the same scenario for years has different requirements than one that needs to support evolving mission profiles. Reconfigurability matters more in the second case than the first.
What's the Actual Timeline?
Precast modular construction generally installs faster than cast-in-place. If timeline is a real constraint, that's a legitimate factor in the decision, not just a nice-to-have.
What Does the Site Actually Allow?
Site conditions, access for installation equipment, and space constraints can favor one approach over the other independent of training requirements.
There's No Universally Right Answer
Both approaches are legitimate engineering choices. The right one depends on specific answers to these questions, not a default preference for either option.