I totally love POSTMAN. The collections thingy is really cool.
I'll give REST a shot too, though :).
Websecurify looks interesting in itself but requires "access to your data on all websites" permission which means doing a load of research into what it's actually doing etc etc which seems like a lot of effort just to try out a rest client.
Best of luck to them though, Postman made by workflow testing API's hugely more efficient so if they manage to improve on that it'll be a great tool.
I mean, if I have to fill a full request myself, I'd better directly use a terminal.
Right now, POSTMAN fills all my needs, and the alternative will have to be really good to make me change.
Maybe people not aware of postman would appreciate more.