I just went through the process and ended up with a AW3821DW. To me the G9 was just a bit too difficult to drive and not enough games support that aspect. Also it has a few issues ( but then what monitor doesn't?). The LG is great ... if you can actually find one. Both of the Alienware are great and look great too. I was actually about to buy the 34" when the 38" came out. My only doubt with yourself is whether you think the 3070 will be powerful enough for the AW3821DW. It is about 15-20% more difficult to drive than the AW3420DW. If I were you I would go for the AW3420DW PROVIDED you can get it at ~£700. It has been down that low so it should be possible. If you are really flush with cash at the moment or you can't get that price down then go for the AW3821DW. There are a number of threads about all of these monitors so plenty of information to help you choose.