I bought an Olympus 75-300mm lens from them for a very good price.
They offer a good warranty (2 yrs IIRC) which is miles better than most camera retailers. Returns are also generous from memory.
For popular stuff they grade A, B and C etc.
My lens was just listed with no grade so I was braced to return it if it wasn't good enough.
When it turned up it was clean and tidy, fully boxed with caps at a price I was happy to pay.
I've never seen anything I want to buy in the local store but online is worth a browse.
Some prices are keen, some are terrible and the descriptions can be inaccurate or incomplete so pay attention.