I'd recommend something like the Kryptonite New York Fahgettaboudit Mini. No one is going to pick it (but it's possible), and almost no one is going to cut it (but it's possible).

There are only a few locks that have utterly defeated me, and they come in two varieties: rusted to the point that they're nonfunctional, or high-security disc-detainer locks (like the Abloy Protec 2). Most other things I can open (eventually).

¹ if your day to day is like a spy thriller, maybe it's different, but for most people it's not.

@dave

four new antique locks

I know what you meant, but an interesting turn of phrase none the less.

Also, what would you recommend to secure a bicycle? I've been told by a police officer that nearly everything can be brute forced with industrial bolt croppers - indeed, thieves prefer this method to tinkering with fiddly mechanisms.

I often work oil through them to make them work better. Sometimes use degreaser, an ultrasonic cleaner, WD-40, wire brushes, etc.

One of them is obviously voice activated, yes?