Having a stresstful time looking for a new oven - advice needed

klaudiamaria

Hi everyone! I'm a long time forum lurker and first time poster. 
Recently my oven has given up on me completely - it's been on its last legs for quite a number of years, it's a really old one and I figured now I've got a bit of cash spare I can buy a new one. 
Now things like this stress me out and overwhelm me massively.. I had a look on Argos (to get nectar points) and AO.
I get very confused about the warranties - I take it it's best to buy one that has the longest manufacturers warranty? do I really need one if the warranty is only a year and I can pay Argos around £60 for a 3 year warranty?
Also, I did a lot of research and am I right in thinking that the class won't make much of a difference? I am a one person household and probably will be for a while, so I don't be using loads too. 
Is it worth looking at well known brands or a budget cheap one will do?
What are the absolute basics I need and what are the techy-gadgetry type things I don't need?

thank you in advance for all your help.