Your best bet is to get a heating guy out there. Too many variables to size a system and efficiency properly. They all provide free estimates. You can check online but still would need to be properly sized.
I agree with William. Get several estimates from several different heating businesses. Chances are each business sells a different brand name. Each business will come out and give you an estimate based on the needs of your home. You can then do some online research for reviews of a particular product. The estimates are free. We went with a system and business that had parts readily available and 24 hour emergency service.
Any brand suggestions
Here is an article for you:
Do you have a heat pump? or gas furnace? I would not recommend Goodman heat pump! We have had that in our home and it has been awful for the past 10 years and are now replacing it. Trane always comes up as the best! Something to think about.
That is just our experience with it. Maybe a gas furnace HVAC system is just better in general. Heat pumps(which is what we had) aren't very reliable at all where we live because of the weather in our area(Maryland). It is too harsh up here for a heat pump. So maybe that is more of what we experienced and not the brand. After all, Goodman is on the list. I have heard others say this about Goodman but like I said, maybe it is the area where I live. Good Luck!!