i am only familiar with grandis, and if you get one, be prepared, they can be timid. you will not be able to hold it b/c their skin is very delicate and could tear easily. over time, when it gets used to you, you may have some luck, but be careful. also, they are very fast! their requirements are fairly easy, once you get the hang of it. they need higher humidity and a larger, taller cage than the smaller ones. i've done a lot of reading and it seems that the larger species live longer, and seem to be hardier, but others who have experience with the smaller ones may tell you different.
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Lisa

1.0.0 P.m. grandis (Linus)
4.3.0 P. standingi (Toby & Kona and their 5 babies)