I use Xtra as my primary email address. I've had it for 20 or more years and like one other poster mentioned I have used it for a lot of sign ups and also the fact it's too much effort to change I've stuck with it. I may change one day.  If I was starting a fresh I would use an address that was portable.


For an individual I don't see Xtra, Gmail, Hotmail, firstname@lastname etc addresses as being any more or less professional than each other.


Though if I see a business with a @Gmail or @Hotmail address I do wonder about how long term or serious that business is.  For businesses that don't use a @businessname address and use a @xtra or at @Vodafone etc address I see that business as a one man band type of business that probably doesn't have a website. 


In the past I always saw Gmail and Hotmail type addresses as belonging to someone who didn't have an internet connection. Anyone who had a internet connection had an email address like @Xtra, @Paradise, @Clear @Orcon etc. I'm talking about 20 years ago, well before mobile internet, things have changed and the Hotmail and Gmail addresses are now much more mainstream.