I've been trying to decide which Mirage to build. I've got in my stash the Academy Mirage III, in both C & R varients; the Esci and later Ertl Esci Mirage III C/CJ/CZ; 2x Italeri Kfir, and the Tamiya Kfir, plus the Eduard Mirage III CJ, and the Eduard Royal Mirage III CJ. I've 'built' the PM Dagger/Nesher/Mirage III (two different boxings), and I have to say it's the worst kit I've ever touched!
As for the others:
The 1/72 Italeri Kfir is a lovely kit, and quite cheap. New it's about £5, but I picked up one of mine for just £2 second hand. There are no seatsbelts, but else, really nice, with decals for either a 3+1 colour scheme, or a 2 shades of grey scheme.
The 1/72 Tamiya Kfir looks a lot like the Italeri kit. In fact, it is the Italeri kit, but re-boxed for the Japanese market. It's not designed for the rest of the world, and hence, no English. Funnily enough, having the same sealed packet inside as the Italeri, it also has the same decals, but only a colour callout for the 3+1 scheme. Peculiar that. However, being more expensive than the Italeri, best stick to that!
The 1/48 Esci or Ertl Esci kit is lovely, with some conversion kits for it. There's even a reasonable amount of cockpit. The colour scheme is the famous silver with red flashes. However, it does have one major failing: raised panel lines.
The 1/48 Academy kits look to be dogs. Yes, they recessed panel lines, but the cockpit is a joke, and the seat, well, hmmm, a slab of plastic. It'll probably look OK, if the cockpit is junked, but somehow, the Esci kit just feels better.
Finally (from my stash), the Eduard CJ is taking kit technology and detail to a whole new level. Yes, it's £26, but trust me, the amount of plastic you get makes it worth while! The detail is amazing, the quality is top notch, and there are loads of little extras (like masks).
Well...looks like I'm going to be kept busy for the time being!