I suspect that your text differences have to do with the assignment of the hyperlink to the text prior to adding it to the quick parts.
If so, is this what you are talking about happening:
The two lines of text showing the URL do not have a hyperlink assigned to them... in fact I used the first line to add the text to the quick parts and then used QP to insert it a second time.
I then use the QP to insert a third time... this time at the top of the message. I then assigned the hyperlink (thus the blue and underline) and used this to add to the QP (shown in the bottom box of the dropdown).
To verify, please check that text that is suposed to be hyperlinked has that property set when you insert it from the QP and so forth.