I found him yesterday and was quite disappointed with his stock. I had been lead to believe it refreshed every day but it looks like it's every seven! At the moment the only weapon he has is a rocket launcher (don't tend to use these) and the two pieces of armour that are suitable for my classes don't give upgrades that suit my builds. There are about four or five weapons and two or three pieces of armour he reportedly sells that I would love but how many weeks I'd have to wait for those to be in his inventory I don't know. In the end I decided to risk the engram as I have read this is guaranteed exotic but not class specific and everything else you can buy with motes of light is cosmetic. I got the wolf hunter chest which was cool as I switched over finished the half level I had to reach 20 and went straight to 22.