In the last 2 weeks I've really tested my Go, a trip from California to Denver for a couple of days and then a transatlantic trip to damp and miserable Manchester.
The first trip allowed me to see if it would do as a replacement for my Pro 4 for work on the longer trip, which it came through with flying colours, yes it is a bit slower, browsing is slower with Firefox, apps take a little longer to load, compiling in Visual Studio is noticeably slower, but we're quibling over seconds not minutes. It's a lot faster than the core duo I'm writing this on, but you do spend a lot of time thinking if only it had an i5.
First the bad things, the screen resolution is not great for some apps, I found I needed to scale at 100% to get the most out of the device, this is a little small for my older eyes, but great at preventing anyone looking over your shoulder from reading. I think the biggest issue is Firefox, because Edge only wants to synchronise half my links, I still use Firefox, it's certainly the memory hog, far worse than Edge from my experience, if I didn't have 8GB it would definitely have been an issue.
Battery life on the flight watching video was a little dissappointing, I had hoped to get a 10 hour flight out of the device with only a single battery charge, leaving plenty of capacity in my battery pack, watching HD video seems to be the big battery killer, I don't think I got more than 4.5 hours. That said when the lights were dim, I could turn the brightness down so maybe I would have got more like 5-6 hours you would expect, if I'd been measuring it on the latter half of the flight.
On to the pros, it's a pleasure carrying the lightweight device, added to that the power supply is much lighter than the Pro 4. Since my phone and battery pack are USB C I used my lumia dock power supply for charging those (and the Go) which itself is pretty light.
It's also a lot easier to use in the cramped conditions of economy, you can have it on the tray table and still have a drink on the table. It also works well on your lap in these conditions. I didn't use it without the attached keyboard, but I certainly could still touch type, turbulence permitting.
Back on dry land, the biggest surprise was how much power the USB-C port can deliver, I have a USB hub with network, plugged into a USB3 graphics adaptor, it was still able to power it well enough to drive a second HDMI monitor in extend mode. After my tv refused to work with the Lumia dock this backup plan worked well. Even allowing me to use BBC iPlayer in HD mode, fullscreen, without jitter.
For travelling, I think there are a few extra you really would like, firstly for the transatlantic crossing, the battery pack
https://www.frys.com/product/9523082?site=sr:SEARCH:MAIN_RSLT_PG is really useful, especially if finding a working power socket is difficult - I tried 6 at LAX before finding a working one. A USB-C to USB hub is pretty useful, I bought one with a removable cable, makes it a lot easier to pack, can switch between USB-C and USB as well. If using a dual monitor then the Lumia dock is handy, but warning, it does slow down the charging through USB-C which is why I carried the super light charger as well as the dock power supply. A portable bluetooth mouse is very useful and for serious work, you will need the keyboard case - it's simply not worth using any other keyboard, this protects the screen works very well and no problems with dongles or bluetooth connections. If you carry spare USB-C cables make sure they're good quality and work with any battery packs you might carry. I think putting a 256GB microsd card in the slot is quite useful, I then point Onedrive at that drive. I also bought a 500GB Samsung T5 for the trip, very pleased with this purchase, ironically my storage on my devices has shrunk as they've got lighter and SSD has got cheaper, so I'm finding I need bigger external storage and microsds, thankfully both are quite cheap now.
All in all, I think it was a good purchase and is likely to usurp my Pro4 as my travelling companion, especially when flying, except if I was expecting to work for more than a couple of days, where I think I'd still want the power of the i5.