Hi kongwee & cheez,
Thanks very much for all your feedback and advises.
They're certainly most useful and expanded my views.
Do hope my son could take up classical, but with his playfulness, and to sit down to practice hard (classical need this), I'll probably need to give it a good thought, wait and see, in this aspect. He's currently in Yamaha 1st year.
My current Korg T61 (hooked to a pair of KRK 5), could not give him the "weighted keys" practice, and henceforth the necessry feel rather. My kid enjoys fidering with the workstation, more than he practice. Thanks for the leads, and totally agree with Cheez, on techniques focus training will go a long way in the future and foundation. I think (with no offence), "teachers" many, "mentor" really hard to find or come by.
Sorry, back to type. Budget wise, 3~4K is confortable, but hope not to invest twice or more, which would put the CP300 in the range ( I think). Acoustics, say U1 would be in the range of 8K+, I may have to sell my car to trade for it (reality is that it's a big pinch).
Thanks for helping to save money, as I thought the CP5 would be better.
The other reason is, I can still enjoy the keyboard (with minimum possible investment), if my kid decides to quit in his teenage years.
Other reason for putting 2nd consideration to acoustics, is that the better ones is higher in price, the lower ones would need to be "scrap", and re-invest for a better one or one that suits him later.
I'm not in the category to be able to try out and know the difference, so I really depends on experienced "help" from you guys.
Apologies, for a little bit out of topic discussion.
Cheers man.