Request.Form[ddlBudget.UniqueID] vs Request.Form["ddlBudget"]

I've already defined clientidmode="static" at page directive.
string budgetId = Request.Form[ddlBudget.UniqueID];
and
string budgetId = Request.Form["ddlBudget"];
both works equally good , but is  there is some performance advantage of one over the other. I know the meaning of uiqueid, clientid and id. My question is if we have already defined clientidmode="static" at page directive, then is it not better to use second over first performance wise.I am using this in usercontrol.
Thanks

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