dummy question about code and the good practice

Just to be sure about code and the good/best practice.

sometime the code can be like this (eg : Skin Estuary) :

syntax 1 :

xml:
<include content="My_Include">

    <param name="Name_A" value="Value_A" />

    <param name="Name_B" value="Value_B" />

</include>

syntax 2 :

xml:
<include content="My_Include">

    <param name="Name_A">Value_A</param>

    <param name="Name_B">Value_B</param>

</include>

syntax 3 (syntax 1 mixed with syntax 2) :

xml:
<include content="My_Include">

    <param name="Name_A" value="Value_A" />

    <param name="Name_B">Value_B</param>

</include>

Of course I have make some test in my side. All seems to be the same for me.
​​​​​​is there only a reading confort for each coder or there is something to know about a practice vs an other practice ?

Thanks for any answers.