I have an MTB bike that cost me roundabout 400 which I use for general travel around the north London area. I guess you could designate it a low-medium crime area.

I currently use an Abus 6KS 6mm chain with a 6mm Squire padlock (hardened-steel and closed-shackle). But I'm not sure if it is sufficient. I'm just worried that the 6mm chain links might be easily cut with bolt croppers. (I do take precautions and leave the chain well off the ground to deny leverage.) But I've also heard that Abus chains are equivalent to other chains 2mm wider, i.e. 8mm chains.

I don't like d-locks as they are too narrow for many posts. Also larger chains tend to be a bit cumbersome to carry on the bike body. My current chain fits nicely in my in-frame bag. So I'm considering a best-of-both-worlds, one of the Abus Bordo locks, the ones 6 long links.

Would it be worth the upgrade?
Or am I fine with my current security setup?