Anyone install an Ecobee 3 lite thermostat?

[rgG]

Two of my three thermostats are Ecobee 3 lite.
I would like to replace the older Honeywell with one.
How hard is the install?
I do have the C wire, as I read that can be an issue.
Do you have to do much/anything inside the furnace?

The HVAC people we use want $385 for the item and the install
The unit itself is about $150ish, so the install is about $235, which seems a little steep.
The instructions online say it should take about 45 minutes for a DIYer.

I also need to check and see if my EMC is offering any rebates.