Most cases, you do not need strip heat when running a "dual fuel" syatem.
You'll find that a heatpump with a gas furnace for "back up" heat is overall the "best" way to go. You won't use any propane for the "mild days".
If you have a leak, and can't find it, CLiplight manufac. in Canada makes "super seal HVACR", a neat little product that will repair "hard to find pinhole leaks" in your system (and no, it won't hurt your compressor). If you go this route, make sure you get it by the exact name as I listed. They have different "cans" for different sizes of systems, and also for 3 phase equipment (dollar says you have a single phase
As far as equipment lines, this is only an opinion (sp). Your right, alot of it s like cars. Weatherking is marketed for new construction, less "bells and whistles" so to speak (and accordingly, usually less in price than Rheem/Rudd). Air Flow is Lennox's line, that equipment is made by Ducane, out of S.C. Ducane makes thier own line as well. To have some info that even the HVAC contractors may not even know, Ducane will be "co-working" with Armstrong Air (also out of S.C, but different town) to manufacture yet another unit due out next year (Amrstrong also make whirlpool). Carrier has Payne (builders grade). Sears "Kenmore" line is uaually either heil or carrier (if it's tempstar, they "private lable" the line with the sears name).
Also note that with different lines, there are different "bells and whistles" the the dealer can get. This is called "marketing funds", and in most cases, the price of the equipment can determine how many "bells and whistles" the dealer actually gets /forums/images/graemlins/smile.gif
To me, I would put a weatherking in my house. There is not "that much difference" between the Rheem/Ruud line and Weatherking (only my opinion)
Weathking is just another "marketing opportunity" for Rheem/Ruud to gather more market share from thier compitition (say Lennox's Airflow or Carrier's Payne line).
Keep in mind from the example above, I could list almost every "make" who has a "sub line", and who's in "co-horts" with each other. The list is WAY TO LONG, take my word for it /forums/images/graemlins/smile.gif
Honeywell, white rodgers, emerson, a o smith (motors) sporlan, alco, are your most "common" names of parts manufacturers for the HVAC equipment line.
But... if it is a high end" piece of equipment" (such as Carrier), the parts are "private labled", meaning that you HAVE to go back to the manufacturer (in some sort of way) to buy the part. This is where you can really "get bent over" so to speak ("technical" for those parts are OEM, Original Equipment Manufacturer). This is where you may be at the mercy of a "factory dealer" so to speak.
I don't want to "knock" any equipment out there, but in my defense, for my company, I've sold/work with at least 2 very high end lines, and some lines that people may not of even of heard of. We still work with these companies (we were not "dropped", just in different locations in the U.S, we have certain "restrictions" on what we can sell.
There is no "piece of crap" equipment out there (although Haier form overseas just opened up a plant in Columbia, S.C and will be hitting the U.S market hard in the near future, and I don't know about them yet /forums/images/graemlins/smile.gif). You will however, pay more for one name than another in some cases.
Keep in mind, the contractor has to make money as well. It can all depend on what he's going to charge you for the equipment and labor/install. Keep in mind, the installation is the MOST important part of the equation in all of this.