Our most recent 2 homes were equipped with programmable thermostats that did not connect to the internet. We thought they work great and you can program individual days separately along with storing various programs. It lets you program to turn up the heat about 1 hr before you expect to get home during the winter and similarly turn down the A/C during the summer. If you have a seldom used guest bedroom, you can simply close the door and/or adjust the outlet for that room. If you have an older home where the windows or insulation aren't as good or perhaps have an older A/C & furnace that has trouble keeping up, then these devices will probably be of less value to you.
Good luck if your complicated programmable system has issues and you have to spend a frustrating hour on the phone with some off-shore non-English speaking help desk person. You might also have trouble finding a service person who will come out to your house if something goes wrong. Lately it seems service people can't be bothered with small jobs.