I have one spare Raynox and i was thinking to check it first before diving into investment
I think that's a very good idea.
As far as I know, I'm the only person who has actually done a head-to-head test of Mitutoyo MT-1, Thorlabs ITL200, Nikon MXA20696, and Raynox DCR-150. Those results, on full frame Nikon D800E, are documented at http://www.photomacrography.net/forum/v ... hp?t=23898
My tests are not complete and comprehensive. They could not ever be. One or another of my lens samples might be out of whack, or extraordinarily good, or in some other way not representative of its model. The results might come out differently with a different objective, or with a different camera, or with different processing of the images. The list of objections that can be raised is essentially unlimited, and because the results I reported are surprising, they attract dissent like ants to a picnic.
Nonetheless, I have found the results compelling enough that when I personally need a converging lens, I haul out my Raynox DCR-150 and leave my MT-1, ITL200, and MXA20696 in their boxes.
But that's my own decision, for what I do.
When other people ask me what they
should do, I pause before answering, so that I have time to ask one question: "Are you putting together a system to use for yourself, or are you designing a system to sell to other people?"
If the answer is that they're putting together a system for themselves, then I point to my results and tell them what I do.
If the answer is that they're putting together a system to be sold to other people, then I recommend that they skip the Raynox and instead use either an MT-1 or an ITL200.
The reason for that latter recommendation is based almost entirely on psychology, not optics. Because the MT-1 and ITL200 are designed and manufactured for this use by highly respected optical companies, going with one of those is a highly attractive and palatable choice, unable to be attacked or questioned except on the basis of economics. In contrast, using a Raynox DCR-150 looks
cheap and sleazy, despite the fact that it works astonishingly well. Using the Raynox is a really hard choice to defend, and to be honest, I'm getting tired of defending it.
Ultimately it's your money and your choice. Please let us know what you do and how it works out.