Ditto welshwizard's comments.
I've been using Samsung SSDs for over 10 years, never any problems. You'll know SSDs are much faster than spinning drives. On Amazon and their own website external SSDs are around £100 per 2Tb.
Never look back at prices with regret - I paid over £100 for 500Gb just two years ago, and the same for 250 Gb a cople of years before that. SSD capacity is very roughly twice the price of HDD, but far less than it used to be and worth it for speed and reliability, though you'd be very unlucky to have a HDD fail these days.
WD and Crucial (more commonly known for their RAM) are worth a look. Toshiba seem to only do HDDs these days.
I've bought from CCL Computers in Bradford many times, great prices and service - I've no connection other than as a customer.
Avoid Currys. Limited range, overpriced, and I've seen them sell very unsuitable kit to friends and family.