Pros
If you work for the market research subscription sales team on a good product with a decent territory, through hard work and dedication you can earn good money by overachieving your monthyl sales target (e.g. up to 20% commission on a target of £20k new business) The sales process (99% of job is done over the phone) you learn is 2nd to none and is taught to you by really tallented former sales people. It is a good place to learn how to smash the phones, build your process and understand what it takes to become a good sales person. Once you start overachieving your monthly target you get to go on incentives and enjoy yourself.
Cons
As your success is totally based on your ability to sell bang-average data over the phone to companies that won't really be able to use it for what you promise, the job is VERY repetitive and can be soul destroying over time. Some managers make you count the number of calls per day and time of the phone (which is great for new starters, but just too basic for longer term successful sellers). There is no real interest from the company to improve their products and everything is about doing it for as cheap as possible and selling it for as high as possible. You can pretty much sell it for whatever you want as long as someone is willing to pay. You have to learn everything about your market and product yourself which means nobody really starts selling until 9-12 months in. Stick with it and you should do OK but many give up, don't get it or simply do not have what it takes. There are a few good people there but hundrends of fools who don't know what they are doing and are desperate to keep their jobs so aren't interested in the greater good. Keep your head down, work hard, make the right friends, learn your trade and go on to work for a "real" market research company.