The major risk is when you need warranty repairs, thus a brand without official representation in UK is out of question for me.
Also, saw here that System76 is just not worth in terms of quality/price:
For the money that I have spent on this machine, I would say that the overall quality of the material, keyboard and overall feel of the laptop it not what I would expect for a laptop in this price range.
To start, there is a fair amount of flex when you press the back the laptop when the lid is closed. You may think that this is a bit picky, but when I walk around carrying the laptop with your hands over the back section, I can feel the case flex a little and I can’t help but worry that I may be doing some damage.
And, the same guy, says you can find the same laptops under other brand in a UK reseller, just not with the same customization level:
This probably comes down to this laptop model being relatively cheap. I found the same laptop available at pcspecialist.co.uk for around £305.00. However, the options they offer for custamisation are lower spec than those offered by System76 e.g. there are no i7 processors available for this model.
You can check this our for yourself here