personally I think a boa is far easier but not nessesarily better.
Lizards including Savs. need to be fed daily or at least every other day and they need special lighting(uvb) as well as much larger enclosures.But lizards can be more responsive to humans then snakes are.
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Boas can be fed once every week or even biweekly, no special lighting other then normal room light.Enclosure size need not be huge, they just dont move about as much.Some boas like Columbians can be very mellow and "sweet".
Both need warmth and certain amounts of humidity according to species.
Its really your call depending on what you want..
I have both (not a sav but other lizards)and it would be hard to decide which makes a better pet but my boa is alot less work..
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