I have owned a peak since 2004 and have done over 5000 hours with it.
I have gone through a lot of belts. I suspect a part of the problem is the belts get too hot and consequently break. I plan to install a fan to ventilate the inside of the belt cage. I am hopeful if the belts stay cooler they will be less likely to break. Aligning the belt pulleys is critical but not that easy to do.
Other minor issues have been
1) Changing the vacuum pump oil is an absolute pita, you have to disconnect everything and jack the pump up by a few inches to drain the oil, then re-install the pump - this can take a few hours.
2) The exhuast manifold kept cracking - I have had my mechanic fabricate an exhaust manifold made from much thicker piping, that was 6 months ago, so far so good.
Excepting the above the peak has been a very reliable machine for me.