Mixing species is generally not a good idea. Tigers and lions are nowhere near each other in the real world. When they are brought into close proximity they can mate, they can fight, but it is not the natural order of things. I wonder if the off-spring are sterile as in most cross-species breeding?
It also can cause other problems. When they bred cattle and buffalo in the West, the offspring all died and suffered doing so.
I do not like forced mutations or animals brought out of their natural environment where they aren't contained properly from each other.
Pets are always your friend no matter what.