I had an opportunity to compare the Casio FX-700P with its soviet clone, the Elektronika MK-85. They have very similar look (actually the MK-85 was designed to have the same user and program interface as the FX-700P had). But the internals are very different: the FX-700P is a calculator but the MK-85 is a 16bit computer compatible with the PDP-11.
It means that the MK-85 is a bit heavier and it has bigger power consumption (it uses 4 battery cells instead to 2 in the Casio machine). The Soviet one don’t have so good display cover and it’s keys look worse but the Soviet keyboard feels better (but it is my personal opinion). It is also slower in the normal mode (it has also a “turbo” mode but I didn’t have an opportunity to try it). Good info about diferences in programming of these machines can be found here.
Unfortunately, the MK-85 has a memory only comparable with the FX-700P (about 2 KB) so it is not possible to run anything but the integrated BASIC here (no UNIX or other operating systems). But at least some assembly programming is possible.