Summit,
You are indirectly asking a very broad question about pump knowledge and expertise.... IMHO
The basis for selection between pump standards depends on the experience and expertise of your specification writers.
The people developing your pump specifications and data sheets should include process, mechanical, hydraulic and electrical engineers who are experienced and know your particular project requirements. Your Plant Operators and Maintenance staff should also have a review.
There is no one single answer to your broad question
MJCronin
Sr. Process Engineer