Not sure about the decals Jan, but I think I saw some of them, possibly at Hannant's site, whilst researching for my Sabre.
In 1/48th scale, I reckon the Academy kit (the 'Mig Killer' one of the two) is the best all round. All the reviews I've read compare it to the Hasegawa, and it comes out better. I've built the Academy kit, and the old Monogram, now Revell kit, and seen the other. The Revell is quite good in parts, bearing in mind it's age, although the intake is 'solid' inside. The Academy kit is a beaut, with only two areas that need attention. The ejection seat is somewhat basic, with the foot rest/restraints moulded onto the cockpit floor, but can easily be enhanced. Also, there's a lip where the intake trunking joins the intake itself, which isn't noticeable until built! But, now that you know, it can be filed and sanded to mate-up correctly! Or, you can fit the optional 'FOD' guards, front and rear. If you're really pedantic, the wing fences could be replaced with thinner, scratch-built items.
The kit includes lots of 'extra' parts, including the engine, which you don't have to fit, or it can be displayed with the rear fuselage removed if desired; the internal fuselage formers are nicely reproduced. There's also a mobile engine cradle in the kit, good for diorama possibilities, or for use, in modified form, elsewhere. The standing pilot figure, complete with 'speed jeans' and parachute, is quite nicely moulded too. The kit decals are mainly reasonable, with all of the stencils etc included, although the yellow Korean Theatre stripes are a little on the thick side. Gun bays are adequate, and easily enhanced, with nice moulded detail on the hatch covers, and a total of eight (!) .50 cal Brownings, and the speed brakes and housings are nicely done.
Overall, especially for the price, I think it's the better buy for 1/48th scale.
Hope this helps.