The spec decides who judges equal and when. Usually the architect decides. Many specs require a substitution request before the bid, by a set deadline.
Example: a spec names one scoreboard model and adds or approved equal. A supplier with another brand submits its data for approval before the bid.
Read the manufacturers paragraph and the Division 01 substitution section together. Some specs name products and allow no substitutions. If your product is not listed, ask for approval in time. Otherwise, state plainly in your proposal that you bid an equal. Never assume approval.