I did the first one in about 10 minutes, the next two took me about 2 minutes each, no problems yet.
I had 3 broken key fobs, electronics were good, but casings were broken at the ring. I could have ordered new covers, but at a cost of around $20 dollars each and $40 shipping to Canada..it was way over $100 with tax. My 10 year old GM is not worth that for keyrings.
This cost $1.25 + tax for wire and I have enough to fix 100 key fobs.