<< Frankly, they all basically suck, but a relapse would be far worse. Best of luck to you and let us know how things work out.>>
Agree, agree, agree! I really hated dealing with retainers and as I've stated elsewhere on the archwired boards, thought a permanent was a great idea. That was of course before my own partial relapse even with the supposedly permanent bonded retainer that came partially un-bonded in spots and I didn't realize. If I'd worn essix at night in combination with permanent (it was never offered), I probably would not be in the spot I'm in now... partial relapse.
So ultimately in answer to the question, I really think removable is better even though I say again retainers just SUCK overall, as does relapse. If you only have permanent, watch everything very closely to ensure all is still well over time.
I only half jokingly said over the last decade-ish of wearing retainers I'd rather deal with the braces than retainers, and now I have that opportunity. I'm weird, but I'd rather just keep the braces than stupid retainers!