I'm updating this review after having spoken with a manager. He understood my concerns, and offered a replacement with a model that uses the style of tip over protection our original unit has (in fact, its very like our original heater). I may take them up on this. But since that conversation, I've looked at this heater more closely, and while my concern is still there, its not as urgent as it was. This unit has a very stable base. It is very difficult to knock over. When we checked it out further, even though you can cause it to come back on once tipped over by pressing in the plunger button, there seems to be little heat. We need to test this out further. In use, it heats the space well. We were in subfreezing temperatures, snow and ice, in our RV for a few days. We used this during the day, and pretty much saved the propane furnace for the night. (We did have the furnance on during the day, but it was never triggered by the thermostat as the Vornado kept things comfortable.) We didn't even need to run the Vornado at full power. We are talking about a 38ft class A and it was comfortable from front to back. So I have to say, other than the tip over protection concern (a situation unlikely to gappen, but you don't want to be that 1 in a thousand), I am impressed with this unit. Need to test the restrictive airflow/overheat feature a bit more. If that really is not working, I'm getting this replaced. ORIGINAL REVIEW - tempered: I have been a customer of Vornado, using a heater and fans, for 2 decades. I always felt I could trust the safety features of their units to protect me and my property against mishaps caused by space heaters, such as preventing a fire if the heater is tipped over. But I question this design.. Vornado has changed the way the tip over cutoff function works. Now there is a plunger button on the bottom that is pressed in when sitting on a surface. While that plunger-style button is pressed in, the unit will operate. When the unit is tipped over or picked up, there is no longer anything pushing on the plunger button from underneath, so it falls back down and all current us cut off. The unit stops working. BUT: If, WHILE THE UNIT IS LYING FACE DOWN after being tipped over, someone or something presses that plunger button back in, THE HEATER TURNS BACK ON forcing heated air against your carpet, floor, spilled papers, or other flammable material. So what happens if a child or a pet tips this over, and manages to lodge something against the button that then keeps it pressed in, allowing the heater to continue pumping out heated air against whatever flammable it fell onto? Why is this not designed to keep the heater turned off until it is returned to an upright position? We have another, smaller, much cheaper no-name brand forced air space heater that has a plunger button on the bottom as well, which works the same way, BUT THIS little heater ALSO DISENGAGES the plunger button while tipped over. If you press it in while it is tipped over, nothing happens. It does not turn back on until it is fully upright again.. THAT is a PROPER tip over protection feature. I do not need to worry about our dog, or other mishap, circumventing the tip over protection feature. When I contacted the Vornado company about this, the initial person I spoke with seemed entirely unconcerned about the possibility their tip over safety feature could be so easily circumvented. He considered it such a remote possibility as to be improbable, and told me this plunger button is working as intended. He also said that the restrictive airflow/overheating protection would kick in and shut off the unit if somehow my scenario occured. How hot would things get before it shut off? He never told me. Would there be damage before it shut off? Would my carpet get scorched? My linolium discolored? What if the overheat feature failed? So I tested that feature. When I placed a towel over the back of the unit to block its air intake, it continued to run, and very quickly there was a burning smell. It never shut off. That feature didn't seem to work at all. So much for relying on this secondary backup safety cutoff. The cheap, little off-brand heater we bought to help get us through some very cold days, before this arrived, hands down wins in the safety department, and this Vornado (and I assume all modern Vornado heaters) falls prettumy far behind. If a little, cheap no-name heater manufacturer could foresee that the plunger button would need to be COMPLETELY disabled unless upright, and implemented such a solution, then Vornado most DEFINITELY can do so too in order to ensure no accidents can occur. BUT VORNADO CHOOSES NOT TO. I will no longer be a customer until this changes. Anyone who owns a Vornado heater with this feature, test this out for yourself, and then decide if it is worth the risk of damage or fire.