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I don't think "advises" match the .org extension, so I have to say the value is regfee. Advise.org would be a decent domain, Advice.org an excellent one.
advises is a word that you use in the format of 'john advises jane to eat less fat' so I think the domiain is not as good as advice.org as weakhealth says
I'f have to agree the plural does you no favours, but with single word domains you will always struggle to find exactly waht you are after
Less than regfee. The term "advises" is practically worthless, then couple it with the .ORG extension, which does not fit it and you've got yourself a bad reg.