You can use tubs as a permanent solution as long as it meets your snakes requirements. My BP does just fine in his tub, however, most of my boas are outgrowing their tubs and need the space of the larger pvc enclosures.
Also, some people like to use PVC for a display cage.
My one bp(soon to be 3!) is in a display tank. He's my pet, and in my room whereas my rack will be downstairs. My pickups will be in this tub set up until my rack is ordered.
Bobbas tank::
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0.1 Dog (Truffles)
0.1 Naked Cat (Mercedes)
1.0 Hamster (Pumpkin)
1.1 Bumblebees (Satyana & Weedle)
0.3 Normals (Shayla, Rita and Althea)
0.1 100% Het Pied Ringer (Avalon)
1.0 Pied (Monsieur Piederoff)
1.0 Lesser 100% Het Albino poss het OG (Tinersons)
0.1 Spider Albino (Ivy)
0.1 Mojave Cinnamon (Morticia)
1.1 Normal BCIs (Damon and Conga)
0.1 Crested Gecko (Natasha)
0.0.1 Rosehair Tarantula (Charlotte)
0.0.1 P.Metallica
0.0.1 A.Avicularia
0.0.2 P.Irminia
0.0.1 L.Parahybona
0.0.1 N.Coloratovillosus
?.?.? ASFs