- i3-7100U https://ark.intel.com/products/95442
- i5-7200U https://ark.intel.com/products/95443
- i7-7500U https://ark.intel.com/products/95451
The most important determiner of machine performance is how much power the CPU can use. CPUs turn watts into performance. A 45W CPU will deliver 3x the performance of a 15W CPU. I'm disappointed that reporters continue to leave out this crucial information in their reviews.
Upgrading from an i3 to an i5 CPU gives you about 10% better power efficiency. Going to i7 gives another 10-15%. So for $650, you can upgrade to the i7 and get a disappointing 25% increase in performance.
DELL is still charging an extra $400 for a 256 GB SSD. Last year, I bought the 2015 XPS 13 and immediately replaced the SSD with a $200 500GB Samsung 850 EVO. Then I wasted several hours using DELL's disgracefully buggy installer. Then it was 5 more hours spread over the next weeks to solve other problems like slow wifi, video decoding becoming slow after resume, and random freezes during resume. I still have problems with sound sometimes not working. Overall, the experience has been disappointing.
It seems that DELL is releasing buggy laptops again this year. These laptops should be usable after a few months, once the Linux community has fixed the worst of DELL's software bugs. I wish DELL would put more resources behind their products and make them really good.