I haven't really ridden it as much as I'd have liked in the last year, so I have to caveat my views with that in mind. I came from riding a Canyon Inflite as a 'second'/winter bike, which was a really great bike. Almost as 'fast' as my proper road bike but with clearances for bigger rubber and much more secure on anything not paved (makes sense, its a CX bike). I used it for bikepacking trips but had always lusted after a Surly, for similar reasons to people in this thread.
I wanted something that could offer more versatility for luggage, rack mounts for panniers or front rack, as the 'second' bike was also used for a commute. My commute went from 10km each way to 25km each way and a lack of proper mudguards was getting annoying (if the Inflite had guard mounts it would be close to perfect). So I thought I'd switch to the Straggler with the intention of commuting on it, plus doing the occasional winter ride on it with guards so myself and everyone else I'm riding with doesn't get caked in UK road muck.
I set it up with the SRAM Rival hydro set from the Inflite, which is probably my first issue and not related to the Surly. The brakes on this groupset are so bad. I've tried a few things and can't get around a really spongy, poor braking setup, especially on the front. It's a 1x group and the shifting is OK, but stopping is poor. Plus, they honk so loudly in the slightest bit of rain - which is great for commuting through the city in the wet.
Secondly, obviously to be expected but it is heavy and it is sluggish. Not really surprised by this but I don't think my tyre choice has helped. Gravel King slicks in 38mm (think they're closer to a 40) - really nice supple tyre but probably too wide for what I'm using it for. Also, really nice looking/rolling tyre but I've had so many punctures on them already. Probably will change these out to something more 'road' oriented in a narrower profile, maybe that will help with the feel of the bike.
The other thing is any off-road riding is conflicted with the crazy dropouts of the frame which I still can't get my head around, it just doesn't make sense to me. I am using the skewers that came with the DT Swiss wheels from the Canyon, but on rough stretches of track, the QR will eventually work its way loose and this means I lack any confidence riding off-road and it kind of takes the fun out of it. Maybe getting a more grippy QR skewer would help here, I've read on this thread suggestions that it can help.
I'm tempted at some point to rework it into less of a 'do it all' second bike and turn it into more of a commuter/town bike, as this is what it is probably better at. Swap the drop bar for a flat bar of some kind and switch to a slightly narrower but more robust tyre. Do something about the brakes. Then maybe it will be different. I recently bought a Supersix Evo as the 'proper' road bike, and have two sets of wheels for this - one sunday best and one for shittier days with a chunkier tyre, so the need for riding the Surly as a 'winter' bike is perhaps negated.
I'm not giving up on it, but definitely hasn't clicked for me yet. Long rant over!