If you don't like it, you don't have to buy it.
I've had that "90's oversize 2.4 reciever" in every car I own including 1/8 buggies and 1/12 on road. Sure it's a little larger than some other micro rxs but I've not had any problems with it fitting in any of my cars. Lemieux and Baker both have one in their NT1 radio box so if it fits in there, it should fit anywhere.
As to peoples comments about modules, yes it is unfortunate that you can't run your mini z on am or swap out your synth module. 2.4 is slowly becoming the industry standard though and will eventually make its way down to even the smallest scales. Besides if you already have a 3PK you have a great radio and don't need to switch up to the 4PK. Some people just want the latest stuff and manufacturers will always keep pushing the technology forward.
Just my .02