Lenovo Carbon X1 Gen4 may be worth a look.  Up to 16gb and you can get it with a nvm-e ssd up to 512GB.  Near to UHD screen size.  It's small/light/powerful.  Downside: not a desktop replacement - you won't find a firewire port or second internal drive.
 
If mobility is important and you'd use a usb3.0 interface, this would probably be a great box for it.

JustGotPaid
This looks like a good one, and it's a Dell. My only concern is when you learn more, it's a 2.10 ghz but is 3.10 with the turbo boost. What kind of difference does that make? Does the turbo boost stay on the whole time when the computer needs the extra power?
 
http://www.ebay.com/itm/NEW-DELL-17-3-i7-3612QM-3-10GHz-QUAD-CORE-16GB-1TB-SSD-WINDOWS-10-PRO-OFFICE-/252300779295?hash=item3abe4c5f1f:m:mEz1r0hmkBR25ldqtfe7g0w

 
I'm a laptop-only user, and if I were you I wouldn't buy this model, just because its display resolution is 1600 x 900. My primary laptop's resolution is 1920 x 1080, and secondary's is 1600 x 900. SONAR's GUI looks perfect in 1920 x 1080.

For mobile recording I recently got a Lenovo ThinkPad P70 (6700HQ) . . . runs Sonar Platinum no problem.
(Though, it does start to choke a bit if I load some plugin intense projects which were built on my desktop computer)
I bought it stock, and have already put in a 500GB SSD drive. It also has a PCIe SSD slot, which will be good for an audio/samples drive when I can afford it . . . and it has Thunderbolt 3 ports . . . so it's definitely built for the future, though there aren't many Thunderbolt 3 audio interfaces in the marketplace yet, as I found out. It works fairly well with a USB2 audio interface for now.

I moved to a laptop lately, Acer Nitro.  CPU   I7 6700HQ
It`s a German model it was advertised as an entry level gaming laptop.
The only thing I added was a second SSD so far, I will add some more RAM in the future.
It's bullet proof for me.
Peace

I use a Clevo shell based around a quad core i7. It was fast when I got it four years ago and still copes well with most things I throw at it. The power adapter is a bit bulky but it's kind of a mobile desktop so I don't mind. I use an eSATA SSD for samples. The OS is on a smaller SSD and I have a second "regular" 1TB drive for documents and recording. I have my main desktop too but the laptop is great for working on location and even finishing projects as it handles all mixing plugins just fine if I up the latency a bit to 256 or 512 samples.

Don't forget to ask Jim Roseberry too!
Or, if this is only very incidental, just use your current laptop. It doesn't seem too underpowered to me, it has double the RAM mine does and probably a newer i7.

Yes, all the highest performing custom laptops are using a Clevo shell.
No off-the-shelf laptop is going to compare to the Clevo running a desktop 6700k CPU.
The only downside to the Clevo is cost.