The unusual thing about specifying hardware in Llandudno is that the front and back of the same house need protecting against completely different things. At the front, the realistic intruder is a baboon, and what defeats a baboon is a mechanism it cannot operate — a slider with a secondary catch it cannot reach, a handle that needs two independent actions, a latch with no purchase for fingers. Strength is irrelevant; sequence is everything.
At the back, the calculation reverses entirely. A rear boundary against the mountain is unlit, unobserved and — for much of the year — flanked by empty houses. That is the classic profile for somebody who has time, and time is what defeats ordinary hardware. Genuine pick and drill resistance belongs there, on the service gate, the back door and any outbuilding, which is exactly what security lock upgrades are for.
Most owners here have it the wrong way round, understandably: they have spent on the front, where they can see the problem, and left the back on whatever was fitted when the house was built. Rebalancing that costs less than most people expect, because the front usually needs a mechanism change rather than a whole new lock, and the back needs only two or three doors done properly.