As with any site I would check each users feedback carefully before you choose to use them.
Their customer support is the worst ever though sellers are honest and reliable. Fiverr customer support should update their service more higher level to resist buyers hatred
How can you say all of them are honest and reliable? That's like saying all ebay sellers are all the same. I've heard plenty of people have problems with sellers not delivering or doing shoddy work but not sure what people expect for a fiver.