ORIGINAL: Sniper151
I have had no experience with the Diamond line, but as compared to Hoyt and Matthews, both Hoyt and Matthews are well established. Parts and repair are quick and in many cases can be done at a local repair facility without the inconvenience of sending the bow back to the manufacturer and both will probably be in business for some time to come. Will Diamond? A lifetime warranty isn't worth much when the company is no longer in business and with few shops handling this manufacturer there will also be few shops familiar with repairs or warranty work.
Do some research... More stores carry Diamond then Mathews and Hoyt (if you exclude reflex)...