I think the laws are fairly worded on this. It's never right to endanger innocent human life.
The real problem with animal testing is that it works toward making the future brighter for many...maybe even all of humanity.
So, how much animal testing is acceptable? This is a tough call. I'm much more against testing for things like makeup and other trivial unnecessary products, but we do have safety standards that must be met.
What about medical testing? Check out this story:
http://news.yahoo.com/s/ap/20060810/ap_on_he_me/toxic_aging
Is it okay to test new drugs on worms? They may be contributing to a cure for Alzheimers. This certainly seems justifiable to me.
What about cancer and AIDS research? Cures, treatments, and vaccines against these diseases cannot be marketed and sold until they have proven their worth.
It's a tough call. I hate seeing photos of animals, particularly mammals, being used in testing. It pains me, and I'm sure it pains anyone with any compassion. But, is it worth it?
It's a very tough thing to make a stand on either way. If you've ever been cured by a drug, or if anyone you love has ever been cured by a drug, know that it was tested and found to be safe on on animals first.
I feel the best way to help animals used for testing is to adopt them once their 'work' is done. You'd be suprised how many labs are now encouraging the adoption of animals once used in testing. See the reference links below.
If you want to give something back to the animals who are making life better for humanity, how about giving them a loving home? It seems much more productive than carrying protest signs.