That lock you’ve linked looks like a ‘coffee stop’ type lock. Ie better for short stops as protection against chancers, but not so good to use for a longer period where people more organised can take the time to go at it. Because it probably isn’t that strong by the look of the strap and lock mechanism. In the uk locks are measured against a rating system, eg gold standard is what you really want in terms of protection as well as what most insurance companies expect you to use.
U type locks are heavy. I mean I guess they varey in weight. But I bought one recently and I found they don’t get lighter the more you spend. In fact it can be the opposite. The most expensive one I saw which was like £150 was also the heaviest. I went from using the motorbike style chan lock which was actually only rated as silver standard. But it ticked a lot of boxes for me. This time I got a u lock from a brand called kryptonite. Who sell a lot of locks here in the uk and are available in most bike shops.
Do you think you’d want to carry a u lock around with you? Will you be staying in places where you can’t keep the bike inside?
Worth a look at www.hiplok.com wearable locks, they seem to get ok reviews. Not as sturdy as a D lock, but probably easier to transport.