The only part that took any time was learning that the retention is adjustable and there are two versions of SPD cleats. Once I got the multi-release cleats and dialed in the retention, zero problems and completely intuitive clip-ins and outs. Even with the original single-release cleats (do they even make those anymore?) and the factory retention setting, I only had two failed clip-outs at full stops.

If you choose SPD, get the multi-release cleats and back the retention way off. Even at the lowest setting, SPD prevents accidentally sliding off the pedal forward or backward. Go for a test ride and keep increasing the retention in small increments until you don't get any accidental clip-outs. On my road and mutt bikes, the setting is so light that I don't even have to think about clipping out. As long as I step off in any direction other than straight forward or straight back, there is only a light click to remind me that I was clipped in. Even as light as that setting is, I've hit rumble strips, potholes, gravel, etc. and never have an accidental clip-out. Anyone who says that SPD trap you or lock you to the bike doesn't know what he/she is doing. I have the retention set significantly higher on my MTB and in a couple of tumbles they have released cleanly. I haven't had a moving accident on my road bike or mutt since going clipless but I've tested release from every imaginable angle and even straight up they release cleanly without excessive force.