I am amazed when I read some bad reviews of this goal yet unique and essential to make hypermacro. Those who do not know how to use the note unfairly hurt. Because yes, it has constraints and limitations: no AF, no focus at infinity, close proximity to the subject, not the stabilization and requires a good previous experience of the macro to x 1 and beyond (with accessories on conventional macro lenses). This is a goal which buys knowingly but delivers incredible results if it is well controlled. The investment is therefore (price + lens accessories, flash (s) or tripod) but it is well worth the shot. Being accustomed to higher magnifications x 2 before purchasing the MP-E (with TC 100 L IS + 1.4 + windscreen macro DCR 250), I have had no problem to use it correctly on . I often use closed at hand between x and 3 x 4. I stabilized myself with my elbows and my knees (or both). I compensates for the lack of light with a flash cobra EX580 II aired. For now, this configuration satisfies me but it's not impossible that I change system in the future to better manage the quality of light. I will try perhaps the focus stacking technique (need a good tripod, a micrometric rail and specialized software). The possibilities are enormous and many different possible configurations. Everything will depend on practice and individual needs.
In conclusion, I advise against this target for beginners or false beginners to the above constraints. Getting into the adventure MP-E requires a time of reflection and maturity. Recommend to the Experts of the macro and those who want to discover a tiny, exciting world beyond our everyday look.