AP sets do come with warranty cards like original warranty sets just that the warranty will not be original, in which the replacement parts will usually or most certainly will not be original. Try getting AP sets from err..... more 'reputable' AP distributors. They will usually have more service centers around the country. Can't say much about water sets but there is always a risk for not getting original sets.

Personally I have a grudge against AP sets and I'm gonna repeat it again coz it really p1ssed me off 

I use to purchase AP sets (about 6 AP sets) only until I purchased a Nokia N82 warrantied by Telstra-AP (they have a service center in Lowyat plaza). It was my first Telstra set and service was horrible...... 
I paid them a visit to get my camera slider fixed. First they tried to cheat my $ by charging a 'dust' removal fee to clean up the dust accumulated in the phone over time for RM80 (i still had 13 months warranty). Then they told me that the WHOLE camera is spoilt and needs an IC replacement (wth? My camera works fine just that the slider mechanism has gone a little faulty. I've checked the schematics and its the slider which is causing the prob. Can't they just change the physical slider? )
Came back to collect my phone and noticed my phone's housing was scratched up and pry marks were visible on the edges of the phone. Technician said its normal procedure. The pry marks/scratches are inevitable   
Walked off and noticed my screen contrast changed. Screen was pitch black (not even the clock is visible. It would usually be displayed) once phone is locked. Went back and inquire about this change and the technician admitted saying he BROKE MY LCD 
Had to make another trip back the next day to get everything fixed again.

So in total, to fix a camera slider, it took me 2 days for 'dust 'removal', 1 housing replacement (probably not even original anymore), 1 LCD change (maybe they butchered my orignal LCD?), so called 'camera IC' replacement and full reformat to re-install the drivers for the new screen. Zzz........

Since then I've never purchased an AP set. Been using originals there after and I'd have to say that the original services which I have been offered are far more pleasant compared to Telstra.

I won't comment on other AP companies. Perhaps some of them are Angels in the business but NO to Telstra zomg 

Midland should be the authorized distributor if I'm not mistaken. Perhaps the other sellers were the ones trying to cheat u? 

Try searching around the garage sales for reputable sellers. They should have the current/best prices around.