I've received my ILR today at Croydon. Since this forum is always very helpful, I'd like to share my experience.
My application was WP + Tier 1. I applied under Tier 1.
Documents I submitted;
-Set O form.
-Employer Letter (stating I'm working since XXX date and still being employed) I've been working with the same employer for 5 years.
-Another signed company letter showing dates of my holidays taken.
-12 month payslips.
-12 month bank statements.
-LIUK test certificate.
-Police Register Certificate.
-A colored absence sheet with dates entered and exit, passport pages stamped, how many days each absence is and reason.
-2 photos with my name written behind them.
-Photocopies of my passport
and photocopy of everything I've submitted anyway which I believe it's quite helpful.
My appointment was at 10.30 am and I was there as stated half an hour early at 10. There were quite a few people. So after a quick airport style security check, I was in queue for my documents to be checked and given a number. The guy was very helpful. He checked my form and asked a few things about my documents. He also asked if I have any traffic offenses or anything. I said no, I don't even have a driving license. He smiled and said yeah they're making very strict rules about it.
Right after that I went to first to floor to make the payment then to waiting area. It was 11.15 when my number was called. My caseworker asked for my documents 1 by 1. It took 5 minutes to give all the documents. I've put everything to individual files with their photocopies.
He said the rules are changed recently so he needs to work on the case and will let me know if he needs anything..
After 45 minutes or so he said everything is fine and he'll show it to his senior caseworker. He sent me to lunch and told me to come back around 2.30 pm.
I've arrived on time again, actually 10 minutes early. Caseworker came back to his desk around 3pm. I'll tell you that was one hell of a wait!

He arrived and he said he was at lunch sorry for the wait, everything is fine and I'm granted ILR. It took another 1 hour to get it stamped on my passport since PEO was very busy.
Overall my experience was nice, it's a fact that Croydon PEO is quite a busy place so I'd recommend to go even a bit earlier to your appointment. I've been there in 2006 and 2007 but never was this busy...
Just prepare your documents nicely organized, have them photocopied and it'll be all good

Good luck to all applying soon...