I've gotten to the point where I can mount comfortably from both sides. Its a good skill to have. I mount a little better from the left side, but both work. I can even mount and dismount from the back on the fixed gears, and have occasionally dismounted off the front (unintentionally ).

The pedal threading issue for 'left hand drive' fixies isn't a big deal. If you think about it, the threading on a regular bike is set up to loosen the pedals as you ride! This doesn't matter because the force of friction that the bearings exert on the pedal spindle is no where near the force of friction holding a well tightened pedal in place, but its one of the reasons pedal wrenches are so long, you need to get them pretty tight to begin with, in order to prevent them from popping off! But of course, that is easier than the opposite threading situation, where the pedals will tend to tighten themselves a bit. So if you do left hand drive, you won't have a problem with pedals coming off, but you may have the smaller, but annoying problem of having incredibly tight pedals. Just get a good coat of anti-seize or grease on the threads, and pack a big wrench.

peace,
sam