Reliable/Best practices for Response Times checking

Hello,

I would like to identify how long took an external service to respond to each request sent during a Load Test via soapUI.

Currently, I'm using the following three methods:

1. Results Screen of the Load Test (the one containing min/max/avg, TPS, etc.).
2. HTTP Monitor for the soapUI project that goes under test.
3. Script Assertion for the Test SOAP Request step of my LoadTest (I have only one such step in my TestCase). The Script Assertion logs the messageExchange.getTimeTaken() for each request into a single text file.

I have noticed that the Results Screen may mention a max value that cannot be traced via the HTTP Monitor or the Script Assertion. Although this is to be expected and normal since the methodologies are quite different, I would like to understand which is the most reliable method for checking the Response Times of an external system.

Thank you!