Impersonating issue aside, let's list the facts.
As what Derrick Koh has mentioned there is quite a fair bit of risk when importing guitars from other country.
1) The shipping charges is the main variable here.
I believe HNLim has contacts overseas and that's why he is able to get it at a cheaper freight and arrived safely in SG.
Without a US counter part, the freight charges alone will kill the deal.
Some dealers actually quote almost 1k or more for the shipping to SG which will make it less favourable to import.
2) The packaging of the guitar is an important aspect.
Without good packaging to protect the guitar against rough shipping handling, there is a very high chance of damage during shipping.
And sadly not all dealers know how to properly package the guitars.
Obviously since HNLim's guitar arrived here unscathed, there is an good indication of sufficiently good packaging during the transport of the guitar.
Say, if the guitar arrived damaged, then the repair cost will make the import less favourable.
Sometimes, e.g. damage to the top, the cost of repair might cost as much as the guitar itself.
Finding a good repair technician in Singapore is another problem.
3) 7% GST is another killer.
Tied the point 1) if the shipping charges are high, the GST will be raised too.
And GST takes into account all the charges paid including the shipping charges.
Take a look at customs website to know the details.
So knowing how to save shipping charges will cut down the taxes paid.
4) Ultimately, the sound is quite unknown when you import guitar.
Although in this case Yamaha guitar are quite well known for consistency, but it's always good to try the actual guitar before buying.
Since HNLim's guitar is available for testing why not give it a try to see if you like the sound.
There is a chance of trying out when you are buying locally and that is a plus.
To summarise, it's not wrong to point out the facts BUT if one does it with an malice intent to smear the reputation of another, then I believe that is not ethical.
Fact is one thing but interpretation of facts is very proned to be distorted into something looking bad.
Ultimately since this is about the guitar selling, whether you like the guitar's sound / playability / worksmanship etc should be the most important consideration.
And since there is a chance to try it out personally, why not contact HNLim and try it out yourself.