Yes, I have two Raynox conversion lenses. They're OK but I don't use them frequently enough yet - just lack of spare time really. You may need a conversion ring adapter.
I have an olympus TCON-17 (1.7x teleconverter) (55mm thread, so i use a 58->55mm downstepping ring thats permanently on the teleconverter). It gives great results and is very light.
I use the Raynox DCR-1850PRO 1.85x teleconverter and the Sony VCL-MHG07 0.7x wide angle converter. The Sony has better build quality but they both are about as good as I can expect in performance. They are definitely not as good as stand alone primes or zooms but at least they give me more options. The teleconverter is the most restricted in how I can use it. To minimize chromatic aberations, which is still going to be more pronounced anyways, you have to use it with an aperture of 5.6 or smaller. This really limits its use in low light situations. The wide angle converter is more versatile and I use it much more often. I really enjoy having a wide angle option and it has really come in handy, especially with architecture and family, group shots. Both lenses suffer from some chromatic aberations but, depending on the image, it is not always a big problem. I figure it is the best I can do right now so I make the best of it.
And yes you will need a conversion ring adapter. This is the part that is the most annoying to me because if I leave the rings on the converters than I cannot put the protective covers on. So it is an added step that takes more time. If anyone knows where I can get some cheap plastic covers that fit the rings please let me know. Otherwise I will probably jerry-rig something that will work.
