It shouldn't matter who fills it....only how much was left in it when it was taken in to be topped off. We looked at the tare weight of the tank, (empty weight), and added 20 lbs. to whatever that figure was. The tank was set on a scale while being filled, and the sliding balance weight on the scale was set to whatever the tare weight + 20 lbs. figure was. (Usually 37 or 38 pounds.) Didn't matter who was filling the tank....once the beam on the scale balanced, that was followed immediately by the OPD valve closing on its own and not allowing any more propane into the tank. Keep in mind that that's the *short* way to do it. What's actually supposed to be done, is the WC rating, (water capacity), is looked at. There's usually a chart next to the filling station that shows different sized tanks on it. "20 pound" tanks are usually stamped with a WC of 47.1 pounds. The chart then shows what the propane capacity in pounds is, and that figure is combined with the tare weight in order to come up with a "weight when full" figure. ;-)

Does it have rotisserie and rear burner for same? Make sure it is complete, you know it's propane and not natural gas? If you can live w/that seems like a great deal. I wouldn't go high-end myself for propane if natural gas available. I've got a PGS k40 piped in, 5 years old, but they don't support their products very well - options/accessories to upgrade over time also disappeared over time.

I have cooked on all three and the TEK IR is the only gas grill that cooks as well as charcoal. It's advantages over charcoal are that it is quick to set up, easy to clean up and does an excellent job of creating the charcoal taste. As many here know, the flavor is created by the smoke from the fat striking the hot surface be it charcoal or something else. The higher the IR energy (from gas or charcoal) and the less the flame, the more smoke generated rather than being turned into additional flame. The TEK creates a great deal of smoke because the IR glass sits between the flame and the dripping grease. On older style IR burners there is still an open flame to ignite the grease drippings reducing the amount of smoke to add flavor. With charcoal, once the embers are glowing red, it is emitting a lot of IR and much less to no flame and hence produces a lot of smoke and flavor. I have owned the FireMagic and I would not purchase another. The burners are cast SS but they still do rust over time and the flavor grills wear out too. They are very hard to clean and the heat was not anywhere near as good as the advertisements. If you are the type that never clean a grill and don't mind a gritty looking grill it may not matter. I am the type that wants it to look clean and inviting each time and the self cleaning feature along with the dishwasher removal panels makes the TEK a breeze to clean and keep looking nice. For me that was worth a lot. The more conventional grills like the Firemagic, even with their ceramic infrared burner are not even a close match.

Many of the grills in my local Home Depot were available in the natural gas model but they were not stocked. I ordered a Vermont Castings from them in natural gas; it was early Spring a couple of years ago and it took about 3 weeks to be delivered to the store. There is an upcharge for the natural gas version which varied a lot by manufacturer - $30 to over $80 if I remember correctly on a $400-$500 grill. The HD blurbs that are attached to the grills specified whether it was available in natural gas. I'm not sure what kind of selection you're going to find at this time of year. It's great not having to deal with propane tanks.