Quickbooks Pro does a great job handling inventory. I've been using it in my business for 7 yrs now. Does everything I need. Payroll, invoicing, accounts recievable, accounts payable, taxes, bank balance, credit cards and so on.
There are Pro and Cons to both Peachtree and Quick Books. I have a buddy that uses Peachtree for his business. Does the same thing I do for a living. He has to back his company files up every two years. That's all it allows you to store on the program at one time. You don't have to do this w/ Quick Books. You can run this program continually forever without having to start over. I have seven years of business on mine and won't have to worry about ever doing this. I don't know if it this is just the version of Peachtree he has, or if it's the same for all versions.