The 105 build looks good but is worth spending the extra on the carbon fork and discs?
I’ve ridden the Roadrat with the Cotic steel fork and it’s as harsh as summary justice, really quite solid, whereas the carbon fork on the X I tried rode fairly soft – makes a real difference off road. I didn’t really get on with the Tektro brakes on the X, I’m used to BB7s, which I think are better but cost a bunch more. So yes but…
I’d definitely go for the carbon fork, less convinced by the Tektro Lyras.
It’s also a bit slacker than a race(ish) cross bike, which you’ll either like or not. I kind of preferred something sharper steering, but it’s quite mountain biker friendly.