Quality Measure for Engineering Services

For product quality I?m used to standard quality metrics (warranty return rate, MTBF, etc) but I?m now working with an engineering service organization. The business is to install solutions. For example installing home or perimeter alarm system. There is product involved in this (camera, sensors, etc.) but really I?m trying to measure the quality of the solution not of the piece parts. I?m struggling with how to measure quality. Ideas to date include:

? Number of calls to call center for support
? Number/hour of field service visits
? Yearly expense for field service support
? Customer satisfaction survey

Are there any obvious metrics I?m missing?

I would say those are acceptable measureables for your service. Some other thoughts:

Response time
Resolution time when problems occur
Tangibles - physical appearance
Reliability - performance as promised
Competence
Courtesy

This may help in thinking about service companies: http://www.juran.com/elifeline/elif...-Control-in-Service-Industries_JMJuran-94.pdf