Yea, I have been using it for most of my electronic invoices, either on-site from my android, or from home.
Very simple enter new customers, create and customize invoice/estimates, and email it to the customer.
You can also add a payment link to the invoice where the customer can click and pay by CC.
i have mine set up with my Paypal acct.
I see that it works with Quickbooks, but I have yet to try it.
It's free to try, and allows up to 5 invoices per month for free, so I would set it up and play with it.
I have never had a single issue with it, and am very impressed with how clean it is, and seems to offer everything you could possibly need.
Cloud based to boot.