Every sauna has a prime seat, called the "filet" seat in the sauna industry from what I heard from the carpenters who build them. Depending on someones seating style, its good to know where the door is in relation to how I like to sit. Some doors are off center and some are straight in front of me. This has a lot to do with the aiming of the far infrared. Sure, the room will still get hot but the proximity of the heaters to where you will be seating. Some heaters are higher than others and others lower.
If the seats are positioned right, its kinda like sitting in a hot tub where the jets just don't output the way I want. At my gym there is always one prime seat where the 2 highest horsepower jets are in one corner and the other ones are about half as strong.
Some people buy a 3 person sauna and one heater is too far to the other side so it makes someone change positions a few times during the session, especially with high fluence rod type saunas.
Its nice when I don't have to be tolerant of my position and can lay down with my oxygen concentrator hooked up to my nose and just relax. I also use a Recovery pump. Its like getting a 2 person massage on your legs. There are a lot of different brands of those too and I am in the process of building a review of those too. The 4 air bag models feel different than the 8 air bag ones but the 8 models feel better but they both really do the same thing for me.
Different brands have heaters placed differently. A corner sauna for example, might have heaters placed totally different than another brand. Corner and 2 person saunas are my most popular sizes that people ask about. I get the best deals on corner saunas so if anyone wants a corner from just about any brand, I get better prices on that model type with 2 person saunas as well. 1 person models are my least popular. usually people wanting a one person gets a dome type. Domes have the most fluence of all, especially the Japanese type.
a word about prime seating:
On some 2 person models I have to move and switch sides cause I get warm on one side but lacking fluence on the other. Its like being under an umbrella on the beach and part of my body is exposed to the sun and not covered.
I don't want to be detoxed on one side and not on the other. I need a balanced detox. It's not just about comfort. I want to lay in there and relax.
If I want the most fluence I'd get a dome sauna. Fibrin, mucin, and globulen. That puffiness under the chin infrared rays usually are not penetrating that with the dome.
Note: the prime seat is usually known as the seat right in the middle of the sauna. This is where even if a sauna is a high EMF sauna it will have low EMF in the prime seat. This can be misleading as if someone sits right next to the right or left side, those heaters usually have higher wattage on the sides and they often have high EMF. The heaters in the back are usually lower wattage as they are right behind the person next to their skin.
There are many different seating positions for each brand of style in relation to the heaters.