Just thought I'd reply to my own post here as a warning to anyone else thinking of buying from Sighterz.
Despite their 99.4% good feedback, I would be VERY wary.
I plumped for the lens at a very good price.
About five days later I hadn't heard from them, so queried the fact that I'd had no mailing notification or tracking number. A reply came back straight away with an excuse and a tracking number so it felt fine.
After a couple of days I decided to log into Hong Pong Post and find out if the package had moved - or if it existed. They replied 3 days later saying that they had no record of that tracking number at all.
Alarm bells went off big time. I contacted Sighterz straight away who said they had already opened an investigation with Hong kong Post and I would hear from them again within 2 days. I gave them 24 hours to sort it and I had an email this morning saying Hong Kong Post had completed their investigation and confirmed that the package had been lost. That investigation took less than 24 hours!!!! (I don't think so)
Sighterz refunded my payment in full straight away, so I didn't lose out, but why do they bother? This is either downright dishonest or just plain incompetent.
Be warned.