Not sure if you made any headway with this issue but I took a look at the last log.txt file you posted in this thread and looked through it. It is quite possible that at the time of the crash, it may not be SMP that causes it directly, but rather indirectly. Since you have many other plug-ins running, they are all competing for processing during your flight, including SMP. The possibility that another plugin is processing at the time that SMP is wanting to refresh, that this could be causing your crash, which is evident with the last line of the log (the XPLM plugin, which I believe is the X-Plane Plugin Manager).
With regards to plugins, no matter whether or not they are commonly used, the fact remains that not everyone will have the same results using them. Past historical discussions about users' systems vs. performance & stability benchmarks, indicate that since every user's system is different, coupled with the fact that we all have varying system configs for the OS and any other programs that may be running in the background, can have a deciding factor on crashes. One question that I didn't see asked was whether or not your system is overclocked, and if so, to what degree of overclock is in place as well as how stable the overclock is. I've been around the bend many times over the subject of overclocking cpus and gpus and I can tell you that not enough proper testing of overclocks can exhibit strange results. One easy way to check the stability of X-Plane, is to run a scenario and then hit CTRL+SHIFT+F on your keyboard, to get your cpu and gpu timings. Obviously the lower the number the better, but more importantly, compare the two and see which one is higher. Depending on which is higher, is dependent on your rendering settings. There are plenty of helpful tutorials out there to help decide which settings to adjust, but as a base. If I were in your shoes, I would visit the render settings, bring down some a notch and see if that might help.