Pros
I started Dot Ones as my first role, and in the 20 months in the company, developed a vast range of skills in many many different areas in IT. This is not, I REPEAT, not the kind of place you can sit around and expect things to happen. I learnt quickly that the place is run as a very large scale helpdesk, but with only a few engineers (often round 6-10)
I would recommend the role to anyone if they wish to start and thrive in the IT industry, but for myself, found its a great foundation, but not the end goal.
Cons
Many processes can end up putting a lot of stress on engineers. For example, first line engineers have a requirement to answer calls on the first ring. If one engineer is on the phone, and another is busy/on lunch etc, it doesn't matter what you are doing, you need to get the call. This means a lot of wires are crossed and many cases will be left mid work,