Also what i came to know is that when u r viwewing a dataset in view mode,then the whole dataset(say of 10000 lines) is sent to the main memory.
But with browse mode,only the page that u r viewing is in the main memory(like 17-18 records on single page) and rest of the records are in buffer.Only after pressing pagedown u r calling next records into the main memory from buffer.
So if ur intention is only to view a dataset better go for browse mode.
Note: Not necessary criterion for JCL or programs as the max lines never exceeds more few thousand lines.
Correct me if i am wrong.