Pros
Great working environment and relaxed, informal atmosphere. Company culture of conscientious working is clear, simple and generally well observed. Some unique characters that are actually really fun to work with. Good variety of people - massive range of ages, races and backgrounds and a pretty good gender split for an IT company (Marketing team is hottie central). I found everyone there to be genuinely helpful. My manager took a genuine interest in my career development (can't speak for all managers obviously) I felt valued as an individual here. Good benefits - everything you would expect and more - free Virgin gym membership, free massages, on-site gym, discount schemes with local retail outlets, travel insurance - the list is endless. Lots of fun stuff - Quarterly team building events, free food etc.. 25 days holiday from the start with the option to salary sacrifice for another 5 days, plus your birthday off. Very understanding when it comes to WFH, flexible hours etc - great for parents. The Rackspace name on your CV attracts a lot of attention from recruiters. Earlier issues with too many layers of management have been recognised and are being dealt with..
Cons
No salary increase in almost 2 years. As with most big companies, massive segregation of duties exists, so in all roles there is restricted variety, which won't suit everyone. Hayes, the area in which the office is located, is a bit rough. The internal ERP system, automation and tools that employees use to support the Customers have not scaled well with the company's expansion and are only marginally fit for purpose - malfunctions are regular, forcing frustrating manual workarounds. Corporate strategy was very confusing in 2013/14 - they couldn't decide whether they were a hosting company, a software company or a services company. The company slogan was changing every 6 months. Things have settled down a bit now, thankfully.