When it works it's flawless. When it doesn't it's a big hassle. I have had both good and bad experiences with them. Last transaction, they stiffed me for $40 claiming they unlocked an already unlocked phone. Weird. They refuse to refund my money.

I've used this service twice, received correct codes on both occasions. Took a bit longer than expected, but otherwise I had no problems.

The glowing reports seem unlikely to me, having had a very poor service with them taking my money, not providing a code and not giving a refund.

I did not have any problems with my code on a Galaxy S3 I requested it and boom instantly got the code very fast and no problems with it. Also my Son in Law used this company and he had no issues with his unlock. I think mostly is either people don't follow the instructions properly or they don't know what they are doing my opinion anyway. I don't think that this company would sell you false information and I have spoken to others about this and they never had issues..

I have had a couple phones unlocked by them and have never had a problem! I am so not tech savvy so I don't know why others have trouble with it but I would certainly have no problem using them again in the future!

Perhaps it's instant gratification wanted? I had an older phone that needed to be unlocked, and knowing that it would take longer than usual, I patiently used another phone. Once I got the code and instructions, I read them carefully to make sure I knew exactly how to follow the steps. They provided different instructions for different issues, which was quite detailed. I also recorded my entering the code just in case, and was successful. Maybe others have problems that a code unlock won't resolve (ie, bad ESN, bricked/locked phone or SIM, reported stolen, etc). But this should be known before trying to unlock it.

I think the number one problem could be that people make an error when typing the IMEI of the phone (serial number)
Also, each phone can have a different process, so I can see how it could become a little tricky for people who have never unlocked a phone before.
I worked in the cellular business for a long time and used CellUnlocker.net many times. There was one time that they could not get me an unlocking code and they returned my payment.

Not sure why people are having issues. It was so simple. I usually say that technology hates me, I usually need my husband's help to figure things out. Lol. Not with this. Straight forward and easy.