tempo setting

[PMA]

Hi List.

This is a question about notational judgment.

I have a several-bar phrase in quick 5/8 time
(qtr. + dotted qtr., but quick enough to allow
only one felt beat per bar), and want to give
its first bar a tempo spec equivalent to

            <full-measure-value> = 80

So, how shall I specify that value?  I figure my
options are:

1) "Meas ="
2) { \note #"4" #1 } tied to { \note #"4." #1 } "="
     or simply
3) { \note #"2." #1 } "="

I tend to favor #3, counting on the original
meaning of the Dot -- to lengthen to some
needed if not-quite-metrically-exact extent.

If you saw that in a score, would it strike
you as sensible, or just wrong?

Thanks for any responses.

Pete