[Galah]

OK, I have read your responses (thanks ) ) and I Is there anything else?

Actually, yes, there is: with extension tubes you lose "infinity focusing", with teleconverter you don't.

Bosaiya, at this stage, I'm only interested in "close focus", as opposed to actual "Macro", so bellows would be overkill for me at this stage.

It would seem that some practitioners are not overly fussy about their choice of equipment (close focus lenses, tubes or tele-extenders) and some mix them and match them at will. See the attached link (once open, make sure to go on to "part three":

http://www.shutterfreaks.com/Tips/tomhicksmacros.html