The Mapex seat back and the mount. To remove the backrest, the entire large black knob must be fully removed.
Mapex uses a four-legged, double-braced base. The base is highly stable as long as you are on a flat surface. If you perch your throne on the edge of your drum rug, and the rear leg is off of the rug, you may experience a small amount of rocking. The spread of the legs is nearly 23”. The base does not fold as compactly as a typical tripod base. The backrest assembly does not fold. You can remove the backrest completely by removing the backrest from the seat by loosening and completely removing one large bolt underneath the seat. But be careful not to lose the bolt and washer.
The throne height adjusts the same as the Tama, (acme-threaded rod) with a range of 19 1/4” to 26 1/2”. The Mapex throne is lighter than the Tama by about 2 pounds, weighing an approximate 16 lbs.
The seat attaches to the base via a single bolt that tightens against the top shaft of the base. This method of fastening the seat to the top post seems to be a weak point in the design of this throne. From experience I know that if this bolt becomes loose, over time the entire socket/post fit will become worn and, therefore, looser fitting. Mapex does attempt to mitigate this shortcoming by including a memory-lock feature of a key collar that fits immediately below the seat mount.
You know what they say about opinions, but I will nevertheless offer mine after having owned both of these two thrones for the better part of a year.
The Tama seems to be better thought out: the adjustments of the backrest up and down, and also forward and back are a step ahead of the Mapex. The backrest also folds forward for packing. My experience has been that even though I can place the backrest exactly where I want it, the Mapex backrest is simply more comfortable. I also find the cushion of the Mapex softer, yet supportive, and it is my choice for a long gig. Neither throne is very portable. I use a soft 16” tom case to transport the seat, and place percussion instruments around it wrapped in towels.
I am 5’10” tall, and weigh about 150 lbs. (I am Capricorn and enjoy mountain hikes and camping). I play mostly heel-down on the bass drum and a combo of heel-up and -down on the hi hat. I have a ‘flat back,’ in that I have very little lumbar curve. Any number of factors related to body type (height, girth, weight, etc) may change your experience significantly.
I hope this information helps you decide what to buy. Feel free to ask any questions I did not answer.