non-jvc manufactured battery vs jvc data battery, is it safe?

Hello,
I've got a JVC GR-DF420EK Camcorder and I'm looking for a BN-VF733U battery. I've found the original from JVC costs £95! and the cheapest from ebay a non-JVC battery costs £22 incl. delivery from Hong Kong. The manual states non-JVC batteries can cause damage to the internal charging circuitry. Has anyone used these cheap generic batteries in JVC camcorders that use the new data batteries and what was the result? Thanks.

http://cgi.ebay.co.uk/ws/eBayISAPI.d...528978840&rd=1 £22
http://www.jvc.co.uk/product.php?id=...100016&eshop=1 £95
http://www.digitalmediastore.co.uk/p...roducts_id=821 £46.99