The company was caught completely flat-footed when Cyanogen went commercial, pulled the rug out from OnePlus, and signed an exclusive deal in India with a competing handset maker. This has thrown software efforts into a panic as OnePlus now unexpectedly finds itself having to rush-release its own Android mutation, OxygenOS. So now the the OnePlus software support, once thought of as super stable, is not. Those who have lots of time on their hands researching and installing ROMs should be OK, the mainstream will suffer through this transition as we witness one more Android fragmentation. Whoever is in charge of OnePlus's corporate partnerships should be long fired by now, yet no such penance is in hand.
This has been a non-issue for me. I don't see any compelling reason for me to move away from the installed Cyanogen to OxygenOS.
Add to this the fact that the field of "near-flagship-features-at-midrange-prices" smartphones is about to get very crowded, and some of the other vendors have the benefit of retail access (instant availability) and local warranty support. Within the next month or two, don't consider the OnePlus without also having a look at the Asus Zenfone 2 with 4GB RAM, the Huawei P8 and the 2nd-generation Moto G. More intrepid shoppers will find even greater choice from domestic Chinese vendors such as Xiaomi and LeTV.
Being a WIND Mobile customer has its challenges, the biggest being that I can't buy any phone and expect it to work on their network. It's very time-consuming to dig up information on whether a given phone will work on that network or not, especially for phones from the myriad of domestic Chinese vendors.
This has been an amazing phone but I don't have much to compare it to. I let a friend who was interested in it play with it and he was amazed at how responsive it is. The only concern I have about it is how repairable it would be in the event of screen breakage or other damage. My son put his HTC One M7 through the wash in his jeans and took it in to get it repaired. Three repair shops told him the same thing, "Those phones are not repairable because of the way they're assembled." I just read that the M9 received the lowest rating possible for repairability. I'd rather not treat these as disposable devices, though that seems to be the direction all smart phones are going. I have no idea how repairable the OPO is so that is something I will be looking for the next time I buy a phone.