Not bought anything in the hi-fi line from them but the method I used to purchase telephones for the home, a digital camera and a smart TV was to go on Amazon (or Comet) and by filtering for your budget read the reviews from customers. I'd choose to take note of items that have a fair number of reviews in order to get a feel for what would work best for you. You can then easily buy the goods cheaper from somewhere else if possible. I generally find Amazon reviews to be very accurate though you do get the odd idiot with a daft complaint.
Nothing wrong with Argos if what you decide to buy does the business for you!
“Every piece of music is a rehearsal of one’s life,” - Sir Colin Davis