SSH for me, but not because it is better in some geeky way. Its because all the web UIs suck so bad its unreal. When things go wrong good luck trying to fix it. I like to know what is happening and see how the server responds to the changes that i make there and then to fix it when it goes wrong, not to see some weak error which states "request failed" etc when you try and do something leaving you no no path at all on how to fix it. Things may have improved somewhat since i last used any of these, but another issue is the (I did have "major" here but this was back when 1gb of ram cost "alot") resources these things suck up.
Lets not mention how over priced most of the commercial ones are.