I think I would stick with the M1 if you will be doing a lot of travelling with the case. Although the LZ7 case is sturdy, it will not be as durable as the M1 which will be better suited for frequent travelling, I would think.
In terms of noise levels, its a tough question to answer, its completely dependent on what components you use and how you configure them!
The LZ7 is certainly capable of being very quiet, it has good airflow and is designed to push any waste heat straight out the case to give your components the best chance of staying cool and therefore quiet.
But bear in mind that the open style vents of this case mean that the case itself does not provide much noise insulation, leaving you at the mercy of how 'quiet' your chosen components are even in ideal or open conditions.
For instance, if you pick a quiet CPU cooler such as the Noctua NH-L9i, a GPU which is renowned for being quiet such as the EVGA 1060 (with SC cooler), a quiet PSU such as the Corsair SF450, and a quiet 140mm fan such as the Prolimatech Ultra Sleek Vortex 14 then you will end up with a near inaudible PC.
One last thing to bear in mind is that the CPU cooler is limited in height, so you are limited on cooler choice. I wouldn't really recommend putting anything above a 65W TDP CPU inside this case if you want it to stay 'very quiet' during load. This case is not built for overclocking a CPU + staying quiet at the same time!
I have found that the Scythe Big Shuriken 2 works really well, but the included fan it comes with is audible even at idle speeds, so I swapped it for an Akasa FN078 which gave a pretty much silent combo. It managed to keep an i5-6500 under 50C during Prime95 + Unigine Valley testing with just a fan speed of just 900rpm.
