Was at the shop just after Christmas. What you see at their online shop is not necessarily what's available. At least two lenses I wanted to buy, AF Nikkor 50mm f/1.4, and one discontinued MF Nikkor 135 f/2.8 that were - and still are - listed on their website, but were not in stock. Other lenses I saw on the shelf (eg. MF Nikkor 135mm f/2) are not on the website.
Yup, prices are cheaper if you are there in person, but as noted by mcn and others in previous discussions, you must specify international warranty if you want it. Bought a lightmeter, but had no warranty at all (grey set?) except for the mandatory 7-day exchange policy all shops must have in HK (for tourists). Also charged 2% for credit card transaction.
My own impression is that the online shop for Tin Cheung seems a bit iffy, especially with regard to stock availability, and mcn's experience of not having any reply to queries.
Might I suggest, if you are willing to spend ~$700 for an online purchase, why not buy it in the BnS Forum? There are usually a few on sale. I have this lens too, and it is not likely to be prone to mechanical problems, and I have not heard of any variable image quality issues. At least you get to inspect the lens and have less to worry about damage in transit.
