Pros
You have the ability to work by yourself without much contact/interference from supervisory management - until you get behind and then you feel like a target is on your back. You get to learn and perform a ton of mechanical, electrical, plumbing, materials management, chemistry work, which is really rewarding if you like that. You get to use a huge range of customer service and communication skills. You literally learn new things almost every day. You're by yourself and if you're a solitary sort of person, that's worth it's weight in gold. The benefits are those of a major world company.
Cons
if you like to work independently and actually CAN manage/schedule yourself, priorities, time management, etc. -- you should be okay. If you CAN NOT work independently and manage a route of 70-100 locations, you will be DROWNING in misery in a NY minute. You do EVERYTHING, from installing machines/equipment, to fixing them 24/7, to having selling quotas for products, to dealing with trying to collect from many deadbeats, to being given unrealistic sales quotas (meaning you will almost NEVER make more than mid-to-upper $30K range - for a CONSTANT on-call experience which leaves you miserable even when you're "off duty" (which you never are.)