Just so you know sellers are allowed to import feedback onto ioffer which means basically good feedback doesn't mean anything. They also try and hide the negative feedback and make it hard to search it out when viewing the ratings this seller has many bad feedbacks but ioffer hides them all on the last pages of feedback.
The guy is also selling those proof finish Prospectors, which I believe I've read are fakes. So I may steer clear. Could be all fake stuff. Take a look: http://www.ioffer.com/i/1oz-engelhard-prospector-silver-bullion-rounds-173929447
good call, looks like they order the feedback from 5 stars at the beginning to the 1 star ratings at the end....check out his last few pages of feedback and you may want to getting it from him and go straight to the manufacture's website and pay a few bucks more to make sure you get what you pay for.
We talked about ioffer.com a few days ago... it's rated at the bottom of the barrel: http://www.cointalk.com/t203215/