I must give DVLA a little bit credit in that most times I rung in recent times I got someone helpful on the phone.
First registration for my c5 being the reason I rung. It did all take weeks to do though. They unfortunately sent everything back (after about 5 weeks..) because a letter enclosed didn't have a date on the letter. This was frustrating as I found it inconsequential to my application. On sending it all off again I was able to get updates on the phone ok after a few weeks. However, on finally receiving my V5, they suffixed instead of prefixed the S for 1998. It therefore looked like a 1978 S. Great.
On firstly ringing about this I was massively annoyed to be told I'd have to write in about it and expect to wait another 6-8 weeks! I however rang again and got someone much more helpful who seemed able to open a case about it and said they marked it as priority and they gave me a case number. I was concerned it might still be a lengthy process to resolve but to give them their due (on ringing again..) they said it was almost sorted and verbally gave me the correct new reg number. The new V5 came a few days later in the post. One thing I don't understand is why all I have is "CORVETTE" only on the V5. No sign of "Chevrolet" and no "C5", both of which were on my application. Doesn't really matter though.
This was just a few weeks ago. The saga continued when I went to apply a personalised plate. The online system wouldn't let me (seemingly because of incidences attached to my recent application) apply the plate to my car. Again the first person I spoke to said to post it in and allow 6-8 weeks! Aaaargh!!
I have had to send it off to them to do with my retention certificate, but I don't think it'll take forever (hopefully..). There is no reason I can see my plate won't be applied ok.
So that's my DVLA saga. not awful, not great.