Modelcraft is the only manufacturer of a 1/48 Twin Mustang.
I would say what you've been told about it in the above postings would be accurate to any Modelcraft offering. Very rough in spots and not for the beginer.
I'd also say get some aftermarket decals if you go after this kit, The Modelcraft kits I've built have no problems with the adhesive qualities of the decals, but they do have the strange tendancy to stretch out of shape when you try to remove them from the paper, no matter how long you had them in the water.
Lastly, customer service is not a priority with Modelcraft. If you find a part missing or damaged, be prepared to find aftermarket or make scratchbuilt replacements. You'll be very lucky if Modelcraft replies to you at all for requests for replacement parts.