I'm currently a third year Psychology student at Lancaster University, and whilst I can't speak to studying Computer Science here, I can tell you what it's like to study at Lancaster in general.
We have an amazing campus, with great facilities. Our library is home to a wide range of resources, and has different floors depending on the work environment you need, i.e., group work, quiet, silence. The buildings are modern, and there are so many places to study, eat, or hangout with friends.
The teaching quality is amazing also, and the staff provide constant support. The staff are available outside of timetabled sessions to go through things with you, and you know you always have someone to ask questions to.
My experience at Lancaster has been really enjoyable, and I'm really glad I picked it as a place to study.
In terms of choosing between two universities, I would suggest making a pros and cons list, and visiting both universities, if you are able to. This can really help you to get a feel for the area, and can help you invision yourself studying there in the future.
I hope this was helpful, and good luck!
~ Cathryn (Lancaster University Student Ambassador)