The Windows Central forums members have been asking this question. Is it a good upgrade from my old Lumia xxx? Should I buy one to see me through until the next flagship device launches?
"I'm wondering if the 640 might be an acceptable, temporary replacement for my 920. At the $150 price I could buy off contract and wait for the promised flagship this fall. While the specs are definitely low/mid range for current hardware how do they stack up to the 920 that's almost 3 years old." - forums member todd7900
On the face of it the Lumia 640 is capable of going toe-to-toe with even the goliaths of previous generations. Compared to the Lumia 920 in question you're getting, firstly, a new phone, a bigger display, microSD card support and the latest version of Windows Phone. Let's not forget the devices we saw at the Mobile World Congress launch were running Windows Phone 8.1 Update 2. Something even the likes of the Lumia 930 and Lumia 1520 can't currently boast.
There's no Pureview camera on the Lumia 640, but the 8MP shooter round the back seems perfectly respectible, and while we'll never judge performance on a trade show hands-on, it didn't seem to do so bad in the darkened world of the MWC halls. But for a phone at this price point we're always going to have to put camera expectations firmly in perspective.
Also for the circa $180 asking price you get Glance screen, clearblack HD display and a removable 2500mAh battery. Not too shabby at all for a mid-ranger.
Upgrade perhaps wouldn't be the term coming from a last-gen flagship. 'Sidegrade' might be better suited.
"I have the windows HTC m8 and have had no problems but I really want the 640. Am I crazy to want to downgrade." - forums member ericreinhardt
Here's an interesting one. The beauty of Windows Phone is that the experience in the software is going to be pretty consistent regardless of which device you're running. The M8 definitely has the upper hand when it comes to pure hardware, but the camera isn't to everyone's tastes for one.
And the Lumia 640 will have Lumia Camera 5. Something currently only reserved for the highest end Lumia phones. But the overall experience should be comparable. And the Lumia 640 comes in Cyan!
"The 640 is the phone that finally gets me back to a Windows phone. I think this could be a home run for MS." - forums member sdc1
What about coming over or coming back from the competition? Just as the Moto G provides the best of Android at an affordable price, the same can be said of the Lumia 640 with regards Windows Phone.
It also fixes some of the flaws with its predecessor, the extremely popular 630/635. There's a front facing camera and a rear flash for example. Converting people from Android is still a monumental task, but for people who got bored and tried something new, is the 640 a tempting enough offering to bring them back?
With the Lumia 640 starting to hit shelves across the world right now there'll be a good few asking "should I buy?" If you're on a current 5xx or 6xx phone we'd almost call it a no-brainer. From something else past or present, only you can make that decision.
But our opinion is but one. What say you? Drop us your thoughts in the comments below or drop by the Lumia 640 forums and join the conversation!