New desktop for CC - Dell? gaming pc? build to order? Meltdown & Spectre an issue

I use Premier to edit, mostly my own HD footage. Currently HD, but would like to be 4K ready is case a client demands it. I also plan to start using AE and also want to be able to commission motion graphics work to bring into projects. I had settled on the Dell XPS 8930, but the memory is only 16GB and although they sell additional (but don't install it) it's not available for a couple more months.

So, do I need something of that spec?

8th Generation Intel® Core™ i7-8700,

16GB,DDR4,2666MHz up to 64GB, (upgraded to 32GB)

256GB M.2 PCIe x4 SSD + 4TB 7200 rpm Hard Drive

NVIDIA® GeForce® GTX 1070 with 8GB GDDR5 Graphics Memory

I have also started looking at machines on Overclockers.

I'm not confident to build my own machine and my head is spinning about what to do, but I do need to buy something soon, as CC won't run properly on my old edit machine, do am carrying on with 5.5 on that one at the moment.

Finally, is Meltdown and Spectre an issue?

Sorry for long post and thank you 🙂