The new Tamiya kit I have no experience with, but it looks great. However, in general, Tamiya kit decals are too thick for my liking, and they don't have seatbelts, usable masks (I find the masks that aren't pre-cut to be tedious, and Tamiya's always lift up for me, whereas Eduard masks and even Tamiya tape never do).
I have the Eduard boxing of The Few. Excellent kit. Some sink marks in the exhaust, which I've heard has been corrected on subsequent releases. The decals are infinitely better than Tamiya, and the detail is fantastic - the mix of raised and recessed riveting is something Tamiya never bothers with, and it really sets it apart. Much more complex construction, but totally worth it, IMO. Oh, and the PE details are also great, and included.
The older Tamiya Mk. I is one I have built, and I enjoyed the heck out of it, but the cockpit is the total wrong shape, like their older Mk.V kits. It should be an oval shape when viewed from the nose of the aircraft, but they have it flare out with the sides of the fuselage, which is completely not how the real ones look.
As for AIrfix...I've built their Mk.Vb. I believe it's the same family as their Mk.I. If so, run away. Run far away. It took hours to get my Airfix Mk.Vb to fit right. Nothing lined up correctly, parts interfered with each other, and it was a complex geometry problem to determine where I needed to sand pieces to get the whole thing to fit. I got it to look god in the end, but I hate that part of modeling, and the new Eduard kits just fit well.