Its not just the support, its the variable quality across products (or updates). I have one of the ~2014 venue 7pros (exact model number escapes me) which came with win8 and I upgraded to win10. I disabled instantgo, and its a fantasic device, the battery lasts for days with my usage patterns, it resumes from standby in a couple seconds/etc. So, when it started having some serious cosmetic issues early this year, so I sprung for a newer one with a slightly newer (and in theory lower power CPU). The new one is a complete POS, the back gets hot, the battery lasts 1/4 as long, it takes literally 10's of seconds to wake-up and get out of the BIOS, the s3 standby options are actually disabled (no bios support), the wifi driver gets stuck. BIOS updates, driver updates, config changes, nothing fixes its load of issues. About the only thing that is better is they swapped the power and windows buttons which on the old one were inconveniently placed.
So, there are reviews of people having similar problems with the older tablet I have until dell fixed it sometime right before I purchased mine. But, good luck convincing dell's tech support that their firmware is a load of crap, and isn't working right. Rather they are like, did it boot, you must have a virus, please reinstall.. I might ask for a replacement but I suspect that won't fix anything.