With short path, the most fundamental parts are glass. When you distill something under vacuum at 200C+ many people ask why I'm not concerned about it imploding. One of the major reasons for implosions is micro stresses in the glass. During the manufacturing process depending on the temperature in the room, the fines of the glass maker, tools, and glass itself, you could end up with form, function, or hopefully both. There are some makers who can make something beautiful, it's art. The best we see are made with what's called soft glass, it yields to work well, reheating and cooling doesn't affect its integrity so much. Scientific glass is what's called borosilicate or quartz glass; Quartz needing higher temperatures to work. They are purified glass types. When made, the glass worker needs to have all his attention on doing something once. because if he misaligns a joint or puts something in the wrong spot, there's no going back. Sometimes you can correct with a little heat but the more you mess with it the more chance you have at creating stresses or warping.
Warping may be as simple as a dimple in a round object or as severe as a joint not being fully round. joints connect each section of glass in the apparatus. They're produced through extrusion or molds creating the basic joint then a lathe comes in and sands the mating surface flat and symmetrical. went the joint is connected there's a fine line with mating two glass surfaces and warping the joint. I've seen a large handful of joints over the years that are not round. this is particularly the case with cheaper Chinese manufactured glass. A lot of what you find on amazon or eBay, and Alibaba is this type of product.
With companies like Summit and Xtractor though, the glass is either made in house or with close partnership with a manufacturer who they've worked with for many years and have a solid bond. Making modifications and developments to bring out better and better products as well as quality control.
Beyond that there aren't many companies I see that have innovated design as much as these two. There are a lot of copy cats in the industry as well as those making simpler designs for the group looking to dip their feet in the industry to see if they like it. If you find a company and feel the craftsmanship is quality then base it on price of course. Dipping your feet in, so to speak, doesn't require much and even Summit still sells smaller kits as well as less complicated setups. Personally I'm not sure on Xtractor Depot, they may offer that as well.
To me though, if you're going to distill something at high temps under vacuum or not, you want something that isn't going to crack or leak on you, so its safer to go with a company you trust over a cheaper Chinese kit you can buy on Alibaba or something. Having a boiling flask crack during a run, though rare, does happen, having leaky joints is extremely common and ways to get around that is to use a grease or sleeve that can make up for such flaws. On rare occasions with improper temperature scaling I have seen explosions and experienced a few of my own. This tends to happen on 20L kits with GL-14 or gl-18 barb fittings that attach to the pump. The sheer size of the system coupled with the decarboxylation process will overload the glass. Glass would rather be compressed then expanded. When we distill at vacuum, the pressure of atmosphere is pushing down on the glass from the outside. This is fine, it is also only ~14.7 psi at most. But just a few psi above atmosphere from the inside can cause a flask or joint to rupture, cause joints to pull apart and a whole slew of issues. So always use a vacuum gauge you trust in a good location and make sure the sop you follow is within safe parameters. I tend to really stretch the boundaries myself, but this is only to see how fast I can really go with a particular setup. Most people on a 20L setup aren't touching into main body temperatures within 30-45 minutes through a complete decarb. I do a lot of testing for people on equipment and these are the tests of glass strength that I need to see so we know a customer isn't going to have unnecessary and dangerous failures.