I (presently - since 2004) have two macro lenses, both Canon. I have basically explained why I bought the EF 100/2.8M - primarily for use as a macro lens on both APS-C and 135 Format, but additionally for its use as a Prime Lens to sit between my 85 and 135.

I have mainly always chosen use Prime Lenses for the majority of my photography: up until 2004 I think I owned only one zoom lens and then, until about 2010, I only owned two zoom lenses . . . I spoiled myself in 2010 and bought a "general purpose" zoom, the EF24 to 105 L F/4 IS USM. Subsequently I bought two more zoom and inherited another one, so I have six zooms now: that still feels quite odd to me.

The other macro lens I have is the EF50/2.5 (and the life size converter). This lens I purchased primarily for my business use: forensic and archival image recording, for example images of Client's artworks, stamps, coins etc. In addition I found it quite an handy lens to have in the bag for a quick and easy close-up style rings / cake champagne glasses shot at a Wedding reception. It is a cute little lens and it doesn't get much use now, but it has always been difficult for me to sell a lens which is little used but still usable.

Prior to 2004, when we cut over to digital, (and changed systems) our 135 format gear was Nikon and we had no Nikon micro lenses, because we had no day to day need for one, especially considering that we had 645 and 6x7 format bellows and suitable lenses if any macros or close-ups were required.

For my personal work, I don't do much macro, but for several years I've has hot and cold thoughts about buying the MP-E 65mm just for the thrill of fiddling at (much) closer than 1:1. After reading Steve's comments I have the hot feelings for the lens again . . . (so if I buy the MP-E this afternoon, I can blame Steve).

It is interesting to read the to and fro opinions about Nikon's Micro lenses.

WW