Good info from Megan and Misty there. A detolf costs £40 and is bigger
If you have the space for it. It's an Ikea glass cabinet tipped on it's back with the door left off. It does mean a little bit of diy to make a lid for it but it is just strips of wood with some mesh stapled on.
I think the Kerry is a lovely tank - I just wish it was 90 or 100 cm instead of 75cm. It is still a good size but it's a lot to spend if it turns out your Robo needs more space and they can be very active.
As Megan and Misty says, there is also the 100cm Zoozone 2 if the detolf is too big for you to fit in. That can be got for about £50. The bars are 2cm though so they need meshing. There is also the Maxi duna multy, which doesn't need meshing but costs about £80.
Zooplus also have a 100cm (well 95cm) tank similar to the Kerry. It has glass front and back and base and wood ends but the wood is all wipe clean and treated with a petsafe varnish of some kind. It has a lift-up lid with small mesh. The Marrakesch. It is quite expensive though - about £130.
Here's the Zoozone - it does need meshing or a robo will escape!
Maxi duna multy - has narrow bar spacing
The Marrakesch tank - currently £119
Skyline Small Pet Terrarium Marrakesh | Free P&P Â£29+ at zooplus!
As you say though, the advantages of a glass tank are you can go a lot deeper with the substrate. It's a shame glass tanks are so expensive in this country. You could also look out on ebay for a second hand 3 or 4 foot fish tank. I've never had much luck finding one - they are either not deep enough usually or ridiculously expensive.
I think the detolf is the best option - it's not expensive and plenty of space. You can even split it in half or section of a third as a deep digging area.
It does need something to stand on really though, which bumps up the price a bit. Two of the small Kallax units cost about £40 making it cost £80 with the detolf - but you do get a lot of storage underneath. A cheaper option is a couple of Ikea lack tables. Or you might have a long sideboard or something it could stand on.
If it was me, I'd go with the detolf - if you can fit it in. It also looks really nice