I have had a Lumia 640 for two years. Phone works well, although is back to the cycle of not being able to install updates because of its limited storage. The 950 is under $300 or maybe less if you can find it. With all the talk of Windows phones going away, should I jump on a 950 before they disappear? Are the 950s significantly faster then the 640s? Should I wait in the hope of something better (although would never spend over $300 for a new phone. My carrier is T-mobile, so I would have to go the route of buying an unlocked ATT phone as I did with the 640. Thanks.