For me it has been a little bit tougher to escalate or change ownership. I had a ticket that the owner completely ignored for 2-3 weeks -- the owner then came back and said something to the effect of him being too busy. In order to get a response I had to call and escalate to a manager. The second time I did it, it was ignored. In the past this always worked to get appropriate responses. Luckily nothing has been too critical, or we figured it out on our own.
There have been a few good cases with Netapp, with the first tier of support being quite good. The product has been so stable and just works generally (many FAS/ AFA), so still happy. Looking at all my other support tickets to other companies they've gone downhill as well -- some have become absolutely useless without a sev1 and absolute hounding with phone calls and emails (Im looking at you broadcom).
Hardware replacements are the same as ever, asup goes out -- part is sent. That's not really changed in years. A few years back -- they redid the website where we went through and updated all the contact information. It's never clear why some hardware triggers verification of contacts and addresses.