A bad idea: take one large, toothy, and potentially maneating predator, and combine it with another large, toothy, and potentially maneating predator to make an even bigger toothy, potentially maneating predator.
A zookeeper in Tulsa learned this lesson the hard way when he was attacked by Rocky the Liger, a lion/tiger hybrid. Somewhere, a Jurassic Park-era Jeff Goldblum is shaking his head and saying "I told you so."
For their part, The Association of Zoos and Aquariums does not condone the practice of cross-breeding deadly animals. The wildlife sanctuary where the attack took place is not accredited by the AZA.
So, amateur geneticists take note: if you're going to pervert nature for fun and/or profit, make sure you give the resulting monster a wide bearth. No hugs, no high fives, and certainly no communal bathing.