No, I'd rather not carry a 15" laptop too and from work. My XPS stays at work, I work at a university, so carry it all over campus which is a massive area, hence the portability requirement. I also don't think the Dell thunderbolt dock plays nicely with bootcamp, I know it's a nightmare in macos.
performance is increased is minor, but battery life is much improved. I've had a 5400, a 7300 and a 7400 on my desk nest to my XPS and I can assure you the latitudes are not better quality than the XPS. The 'business' laptop does not mean better quality, it just means it has things like vpro and a tpm chip, both of which the XPS has and since i have the business warranty anyway, there is little difference in that regard, but the XPS is smaller and lighter for the same spec. Roughly 2mm thicker, 10mm wider, 8mm deeper and 100g heavier, but it's not just that, the 5000 series feels cheaper. Things like the separate trackpad buttons the barrel power supply rather than usb-c, the bigger bezels round the screen, the much cheaper plastic case.