I'm not likely to be doing any more than around 20-23L at a time, do you think it could handle that?
Preboil volume or finished volume?
who really knows.... i'm just not sure id take a chance.
I once pulled the trigger on a cheap "tea/coffee/crabcooker" urn on ebay. If you do a search you'll find numerous threads about this specific item.
From memory, it was 36lt, rated at 30-110deg, heating power was supposed to be 2200W. It had two elements, one 800W and the other 1200W.
Was a big piece of shit, and MOST other people that also bought one agree.
I've learnt my lesson with urns and power vs capacity. Either go with a crown or birko, or get a pot of whatever capacity you think you'll need after factoring in losses, and build an urn yourself. Elements are everywhere to put in a big ass pot.
Whilst it may in fact work (my cheap box of shit did for several brews), there is a big chance that any cheaper urn other than industry standard brands (crown, birko) will shit themselves very early on in it's career.
I'd probably walk away from it.
I've effectively made two digitally controlled "urns" over the past few years for my Single Vessel Recirculating BIAB rig in my signature.
Was really easy to do, and apart from blowing a cheap $8 element in the second brew by allowing it to be switched on with no liquid near it, neither rig has failed me yet.