RIP MacBook

no, i haven't reposted an old entry. my NEW MacBook started acting sluggish, then quit working after five days. wouldn't recognize the hard drive. i took it to apple and they got it going again. thought maybe things had just come loose during shipping. it started the sluggish thing again a few days ago, then yesterday when i tried to restart, it once again showed no hard drive. this time they gave me a new computer, but acted suspicious and said they'd never seen this problem before. i know the first generation macbooks had a lot of problems, which is why i put off getting one as long as possible. anybody else have a similar macbook experience?