Looking to go from Stansted to Southampton on the 27th of this month.

Plugging my day and time in here

https://www.thetrainline.com/book/re...IAkKqFrw%3D%3D

Gives me the below option.

09:30 Stansted Airport to 10:32 London Liverpool Street

Take the Tube from London Liverpool Street to London Waterloo

11:35 London Waterloo South Western Railway 13:00 Southampton Central

1) Does it seem a straight forward enough option or is there a better one that not on the trainline?

2) If I purchase from the trainline I assume I get a printout of some sort. Is this my actual ticket ticket or do I have to some ridiculous exchange for tickets at a desk first(i.e. at stanstead first, then again at the London liver street then again at waterloo) slowing the entire process?

Thanks in advance