As others have said, you're never too old to start using clipless. I converted about 10 years ago ( or maybe more - at my advanced age of 58 the memory plays tricks! ), and eventually persuaded my (much) older brother to try it when he was over from Canada on holiday. He was more than half convinced anyway, as he'd already bought a suitable pair of shoes and fitted them with Wellgo cleats. Whether it was some slight incompatibility between Wellgo cleats and Shimano pedals, or more likely that he'd fitted the cleats back to front, he had a serious clipless moment while on a group ride in the northern wilds of Notts when we stopped at a level crossing. I can honestly say that I've never had a problem; certainly not when compared with using clips and straps.
Due to nervousness, I started with M324s - the ones with a flat side and an SPD side - but the uncertainty of whether I'd connect with the flat or the SPD soon made me change to double-sided (M520 or M540, depending how rich I felt), and these are now on my normal commuter and my "Sunday best" road bike, while the M324s stay on my backup commuter. The Brommy still has standard issue pedals, but these will be replaced at some point with the M520s I bought yesterday. (At a bargain £23.99, including SH51 single-release cleats. Thank you, cycle_promotions! They'll be having one-day sales not far from you, Rowan, on 15th Jan in Coventry and 18th Feb in Wolverhampton).
As Cheesney Hawks says, you may be better off getting some multi-release cleats, at least to start with. Take the plunge, find a quiet road, or better still a cycle track with grassy verges just in case, and start with the release tension set to minimum. Go for it!
