Hi
Yes, but it was a couple of years ago now. Here is my timeline.
My original nationality is Thai. Then...
British citizen : Dec 2012
ILR (unmarried partnership) : Sep 2011
FLR (unmarried partnership): Oct 2009
PSW : Oct 2007
Student visas from April 2001
I met all the requirements on the paper and provided extra documents that we have lived in the same addresses for almost 5 years (they only required 2 years). My only concern at that time is that we only have 1 document which is in joint name (a bank statement with both of our names dated back less than a year) and the rest of the supporting documents were separate letters but always to the same address. Also, we have lived with another friend in the same address during that time and try to keep his name out of all the rental document.
I applied through PEO and it was worth every penny, i suggest if you have the fund do go through this way. I got a result immediate on spot and in 7 days my ID arrived. Much better than being left hanging for months. Also I think it helps a little for them to see faces and recognise that you are genuine (I put on the poshest accent in my life

).
I hope yours gone well. From the look of it, this category of visa hasn't changed much in the last few years. Good luck!