Thai NMB Keyboard Questions

[atx-88]

Hi, a few T40 Keyboard questions -

If a T4X series keyboard has the IBM FRU:39T0519, does this mean that it is a NMB Thai keyboard for sure?

My favorite Thinkpad keyboard is the one on the 600 series (great firm feel, quiet, perfect stroke length) Do the NMB Thai keyboards come close in feel?

I just bought a T40 and found that the keyboard was made in China. The tactile feel is the worst of the any Thinkpad keyboard I have ever owned so I am quite dissapointed. All I can say is that the feel is "generic" and the keys feel hollow. I also found the keys on the bottom left hand corner (Shift, Z, A, Ctrl, FN) all sound VERY loud and loose when pressed. The keys else where and on the right hand side all sound quiet in comparison. Is this common on T40 Chinese keyboards?

Thanks for your insight and knowledge!