I also have a 4-year old XPS15. The SSDs and RAM are super easy to upgrade. There are two internal SSD slots (one shipped empty). Dell charges not-quite Apple-scale arms and a legs for RAM/SSD upgrades, so I bought mine Dell-minimal and immediately upgraded them both and have bumped them up as prices come down for new parts. The upgradability was a major reason I went for the XPS15 instead of the XPS13 (my previous machine)