Being unlocked, it is a perfect go-to phone for trips abroad. As far as hardware, the only "downside" is the lack of LTE bands in it's radio.
SOftware is where it lacks, though. I got this because Oppo promised frequent updates to the OS, and TBH the Android-based variant it came with was not too bad of an experience. Then it became clear that the development team does not really know what they're doing (same minor but annoying bugs with every release, now barely coming through with 4.2, etc). They could have given CyanogenMod the kernel and drivers and let them pick up the development. CM-based ROMs are functional, but still plagued by bugs that come from lack of access to proprietary code.
Basically, their approach (at one point there were 2 or 3 versions of ROMs in development, none out of a beta state) stretched them way too thin, and it shows.
Last but not least, ignoring many requests of just embracing AOSP and let the plethora of apps do the rest was not a smart move on Oppo's part.