I don't think this is a question anyone can answer for you. You have to ask yourself if you're willing to take the risk, because there IS a higher risk with IBM drives compared to others, if you simply look at the percentage of failures. Maxtor promises a 2% or less failure rate for their hard drives, and their 740x drives currently have a reported .5% failure rate since they've come out. I like maxtor because I think they balance cost and performance the best out of all hard drive manufacturers, but I also have a 13.2GB Western Digital that's lasted me 5 years.
If you return the drive, do it fast. Some web sites require you return it within 7 days. If you want to return it, don't forget to get your RMA number, and don't forget that nearly all online retailers will make you pay a 15% restocking fee, even if it's not opened at all. Add to this having to wait again for a whole new hard drive to ship to you (if you decide to buy a different brand). After all of this if you still think it's worth getting a new hard drive then go ahead with it. Just be careful in the future. Generally when you buy online, you have signed your invoice in blood, and nothing can be reverse without paying enormous expenses.
On the other hand, if you are dealing with a fairly reputable dealer, check to see if they will let you 'swap' hard drives, so that you don't have to pay the restocking fee. Be reasonable and it might work, but still be prepared to pay for shipping both ways.
Censorship makes us so much more creative.