I don't think an 80cm cage would be a good idea and it's well below guidelines - some dwarf hamsters will bar chew. That might sound odd when an Omlet cage is "only" 8cm longer, but the Omlet is also much deeper than 50cm with a difference in square centimetres of 980sq cm An 80 x 50 cage is only 4000 sq cm. The Omlet is around 4980 square cm
Sorry Xena's Mum we're chatting a bit - cage chat is always interesting! Dependng on whether you had a cage or enclosure in mind, Here's what I'd do
If you have the space and finances and like an enclosure style - consider a 100cm Bucatstate 2 - about £140
If you want a cage that's easy to use and set up and manoevrable then get a Grosvenor XL which is about £70
If you don't mind the extra cost and like the Omlet with perspex and it's design, you could get that for £135 in the sale
If you find another cheap second hand savic plaza, you could consider spending £120 on full perspex (replacing the bars completely - it turns it into a tank with a front door). But that would be the most expensive option.
Or something else entirely from the cages list! - I'll link it below but I think those are probably the easiest options for a dwarf hamster.
Anyway if you do decide to buy a new cage - it would be good if you use one of the links from here, as it helps the site running costs

But there still some good second hand choices around too.
Here is a list of suitable cages available for hamsters in 2026. Whether you prefer tank style or barred cages, front access or top access, there is, thankfully, plenty of choice in the Uk and Europe. Choice in the US is mainly tanks and tank style or diy. Both tank style and barred cages...
www.thehamsterforum.com