Assuming for a business where you are planning to purchase several, I would expect any major company to have their sales team provide an on-site demonstration and leave the equipment behind for some length of time. Anytime I have done this, I provide them with feedback, especially for products we don't purchase. In some cases, we may only be looking at a single unit but the cost may justify that level of service.
We used to rent more specialized equipment for short term projects. This worked out well.
Recently we bought a Siglent Arb where I work to test the waters so to speak. It was less than impressive but we are only talking about a few hundred bucks and did not return it.
For home, I don't expect that level of service and just do my homework for brand new equipment. If I were to buy a new Siglent scope for home, I would have to get a demo unit. After seeing how poorly the Arb worked and not getting any answer on if the problem existed with higher end models, the risk would be too high. Last thing I would want is a scope where I rotate the vertical gain knob in one direction and waveform gets smaller and then bigger. You laugh but after seeing that Arb, I have little confidence in their ability to get the UI right.
Mostly I buy used, name brand equipment (all I can afford). If the seller states the product works and they offer a trial period, I will take that time to make sure there are no problems. If I find any, I'll try and work with the seller to resolve it. The problem with this is the seller assumes I am some wannabe tech with a degree from a box of Cracker Jacks. Getting over that hurdle quickly is a skill in itself.
I did purchase a DMM from one of the major distributors mentioned often on this site. When the meter arrived, I it was missing screws, broken wires and such. Guessing it was one of the expert reviewers who can't tell a MOV from a PTC that wanted to try it out which included taking it apart. When you have the skills of an untrained monkey that doesn't always work out so well. I still have that meter.