It's all techniques and their is a dozen ways to skin a cat.. Of coils work for you then use em.. Don't try anything new and don't change anything .. All that matters is how you feel and your clients feel about your work.. Not what you use or what bandwagon you jump on.. Their is a lot of guys who enjoy cartridges and only use on machine for all their needs.. Others prefer multiple machines set up different ways.. What rotaries have you tried? I've used and owned easily over 30 so I might have some insight for you.. Currently I enjoy in no peticular order is my dan Kubin sidewinder , my gen 8s and my spectra directs.. I use cartridge for certain things and stick to regular needles and tubes for others.. I still use a few ciferri coils and a few other coils from time to time too