What is more efficient: text(765) or varchar(765) to store a freeform searchable description?

EDIT : To paraphrase quesiton - at what point do I switch from varchar to text and back?

A little background on the question. Let's say we have sales_orders table and we want to be able to keep a note field on the order with customer's or sales reps comments. It needs to be searchable LIKE "%goldfinger's gun%" We know we are not going to have "War & Peace" stored in the field, but at same time it should be big enough to handle a sentence or two.

So which option is:

• faster for reads?


• better at storing data?


• better for full text searching?


• indexing?

Assume MySQL(InnoDB) or PostgreSQL use case