Advertisement I get that slings can 'lost' and hard to feed etc. in big enclosures so I use small delicups as well. However for juvs and adults I think it has several advantages to use bigger (6-7x span or bigger) enclosures than the often recommended 3-4x span. For example when I had my sub adult C. darlingi in a ~2,5x span enclosure she just made a layer of web on the surface of the substrate and often just stayed in one corner in stress pose, never burrowed (even tho it had plenty of depth). But after I rehoused her into a 2x bigger enclosure she made several burrows and webbings and she's more active. So I think bigger enclosures offer more opportunities to a tarantula to utilize. Also feeding shouldn't be a problem, you can just put the prey item near the T or wait 24 hours to find it (my T's 90% find it within 24 hours if hungry). It's also safer and less stressful to do maintance if your T has more space and not near your hands/tongs. So overall I think if you have enough space for big enclosures you can absolutely use them, it won't stress your T (they don't have small enclosures in the wild), infact it can provide more opportunites for your T. Of course I'm only talking about surface area, height shouldn't be more than 2x span. Thoughts?