For three years, I've had cars serviced at Ruby's ARCO in Issaquah for my company. The service is plain and simple, and while the prices aren't at the bottom of the range, they give you what they promise.
The staff are friendly and courteous, and if you are a regular customer, they remember you and make you feel welcome. I've never felt cheated or surprised with additional charges, and if the costs will dramatically increase, they let you know.
I've also gone in there with relatively minor problems. I borrowed a friend's truck, and they heater coil sprung a leak. The pickup was, but the coolant leaked onto the heater and the steam went into the cab, fogging up the windows and making it difficult to drive. I took it in, and he said it would be expensive to fix because it involved approaching it from under the hood, behind the engine. I didn't want to pay for it because I didn't own the car, so he put a temporary sealant in to patch the hose until better help could be purchased -- without charging me.
Basically, you get what you pay for there, and they don't fit the profile of a dishonest mechanic.