Theoretically dropping high pressure across two valves is better than single valve. However, in practice, two valves will not usually control well together unless the process can operate with a very low proportional band with slow response time.
A better alternative is to use a valve with internal multiple pressure drops. As an example, HUSH™ Trim manufacture such valves. This design reduces cavitation, excessive leakage, hazardous noise, vibration and mechanical failures.