Been flying 16 years.

Replaced- 1 starter battery ( it was 15 yrs. old)
3 servo failures (one brand new heavy duty Hobbico, two JR's) Maybe 10 glowplugs, though maybe not that many, I use low nitro, and run rich with 22 % oil.
1 GWS Rx, ( accidentally crushed it with a pair of pliers-don't ask!)
A worn out engine or three.
Worn out squeeze bulb (needed to get a fuel pump anyway it just took 15 yrs. to wear it out!)
1 bad battery pack in a Hitec Tx (bad cell)
Planes to numerous to mention It's been awhile but this one really broke! (see crash pictures- ouch!)
Lots of fuel jugs (empty)
That's about it. Hope your luck changes soon. The quality of R/C stuff is pretty good from where I'm sitting, but you can get a hold of some real junk, in any hobby.

Jetts