I Use a Raynox 150 and find that DOF is a problem I have to contend with.
I have a Vivitar Ser 1 105 macro and Pentax DA35mm lens, both of which are at the leading edge of Macro quality shots.
I feel that the Raynox is not quite at the same level as the above two lens, and, of course, other notable lens.
But, nevertheless, I find the Raynox on the Pentax DA 55-300 (for example), is a fun exercise and produces some very acceptable results.
Taken with 55-300/Raynox150 :
Not a picture to rave over in my opinion, but acceptable I suppose.
DOF problem more than obvious.