poor application and QA of liquid metal is a big one. The foam part isn't sealed properly, which would allow the liquid metal applied to get out from the IHS and damage parts. From what I've heard, it's a somewhat common occurrence. By moving the laptop around, as you should, it would result in the liquid metal to move around and leak out. So if you intend to carry this around a lot, reconsider that choice.
Second, this laptop has terrible RAM. Tech reviewers have seen up to a 25% increase in gaming performance by just switching out these garbage ram sticks with ones that should've been included in any gaming laptop costing above $1k.
Edit: while your laptop may not have any issues during the return period, a lot of people have experienced these problems right after the return period. If you're ok with going through ASUS's long several weeks RMA process just to get it repaired/replaced (with no certainty those problems will not appear again), then by all means buy it. Something to note is that according to reviewers, 1/4 of the buyers do NOT recommend this product to a friend.