I would expect 2 to 4 hours for an install depending on the complexity of the dish mounting. I had the same installation performed a few weeks ago and it took about 2 hours.
It may help you to read some of the installation experiences noted in this forum. For one, there is no "standard" professional install. For example, some installers use a post driver and others will use concrete for a pole mount. Some use solid core copper RG6 and others use copper clad. Some will not bury or fish wires without extra compensation. I have even heard of some installers wanting extra for a pole mount.
I did my own site survey (with proposed dish location), drilled a few holes, and agreed to bury the fairly long run of wire needed. In exchange, I asked the installer to do a neat job. The job ended happily for all with minimal issues. The best advice is to talk to the installer and make sure you get what you want and expect.
As for the two tuners, I would double check to make sure that two wires (or double coax) are used and it is hooked up and working by using the receivers setup menu.
