Everything is a tradeoff. The best option is the true macro lens - focuses from infinity to 1:1, best IQ since its optimized for Marco shooting. The tradeoff is cost - they're the most expensive solution. Extension tubes are best for short lenses, close up filters are better for longer lenses.
Extension tubes have no optics, so using them doesn't affect IQ. It does reduce the light intensity, so you need longer exposures, and AF is iffy with tubes. Also, the working distance (between front element and subject) can get quite short with tubes, such that you can't use longer tubes with ultrawide lenses since you'd need the subject to be actually inside the lens. Magnification is lens native max plus (tube length / focal length) - you can see why they're not very effective with long lenses, the bigger denominator means less additional magnification.
Close up lenses can degrade IQ. The 250D and 500D are double element lenses, not too bad for IQ. They don't affect exposure. Working distance is fixed - 50cm/19" for the 500D, 25cm/9.5" for the 250D. Magnification is determined by focal length - longer means more.
Personally, I've used the 500D on my 70-200 II - that gets you to about 0.6x, and in similarly-framed shots, it was hard to distinguish the IQ from my 100L Macro.