Citeer: "pearcem12"
Citeer: "CassTaylor"Count me in with the stamp collectors; I use Colnect but their stamp catalogue is extremely incomplete, especially when it comes to older "Stamp Duty" issues (British colonies, etc.).
Okay thanks for the info, a lot of these stamps are older British Colonies issue so that is very helpful 
To be fair to them the definitive issues are all there, so unless you're looking to enter some of the larger issues marked Stamp Duty, you're probably set to go; I only have about 10% of my stamp collection that isn't catalogued on Colnect.
That brings up another point; additions and edits take ages (in my experience) to be verified on Colnect, and thus I won't be contributing to them as consistently as I do with coins I own that aren't complete on Numista.