Standard: Had a wooden one, smelled. Was used as heavy plant stand, was concerned this wouldn't hold the weight but is plenty sturdy. Like way front opens down better, old opened like cabinet, just works nicer. Nice that can be dissembled if need cleaned/renewed someday. Also rectangle shape allows for larger box than old that was square that only fit a medium-small pan which isn't great for adult cat. I have a large high side litterbox that fit in this, I did have trim the front and back curled ridge off, but once done it fits so perfect and snug in box on all sides, just beautiful, and no chance of pee getting outside litterbox now. Slides in and out smoothly. like a glove Paranoid from previous experience, I calked the seems on inside after I assembled, but because I was able to fit a high side box in, was really no need. Looks nice, takes care of the eyesore problem. Looks better even than wooden one we had before. And cats like it better with the side vents, yet box still muffles smell more than just a open box. Jumbo: First, the experience with the Standard that owned i guess a year or two now is great as the first day. Works perfectly. Now ordered the Jumbo for another space. Also great. Assembly can be very easy. Skimmed through the book to get the assembly order, ignoring the parts. Than putting it together is just straight forward, only one way it can go, bar codes on the inside, etc. Same with plastic screws, is pretty obvious where the long ones are needed, and where short. I think parts are labeled but I didn't look. Starts little awkward so guess one those things where you get lucky in the assembly flow or struggle a little. just don't assume the top stay down till have all done, almost funny frustrating to have walls up and many screws in only to lift the top and have everything pop out of joint. Also if you don't put the front on till last, don't tighten the front side screws too much because will need loosen to fit door in. Someone complained about the plastic screws but i think a sensible and durable solution and see the engineering behind this to be well thought out. Was kind of dirty inside from manufacturing so I opened box in garage before carrying parts inside to assemble. It was requested I cover up the air/light holes, so I put ouch-side velcro around them. I cut a carbon airfilter sheet into 4 pieces and they just naturally stuck to the velcro. so looks nice, but doesn't let light through so little rude for the cats. really covering the windows is not necessary to cut the dust. it is surprising and counterintuitive how much the cat box's block the dust even with openings left open. but I will leave them covered till person calms down from pervious bad experience with open box. I'll also grab a pack of vent cover filters at walmart use them instead of the carbon paper on the non-visible side sense they will let more light in. I considered gluing or taping plastic tabs on to hold whatever window covers I use, but the velcro idea was genius. Is really better to leave them open though, sadly litter boxes should have some airflow. I've delt with way too many cats for decades these boxes contain the litter chaos as good as it gets. If the cat box isn't cat sanctuary they make you pay. Very big. I carried up steps by myself but most would want two people. sturdy. walls don't fit snug against box the way standard does, but gives room to store scoop inside. Is power cord hole, probably for automatic litter boxes, though you could also mount a small TV for your kitty if wanted to turn the space into a lounge area.