I have no particular opinion on that jumper, OP, as it wouldn't suit me, but I'd just confirm that the quality of Celtic & Co. jumpers is very good. I have a polo neck and a jumper dress from them that I look after carefully and I reckon they'll last a decade or more - unlike anything from H&M or made of synthetic fibres. No itching. No shrinking. No pilling other than where a bag rubbed and I combed carefully and removed the bobbles.
That suits me because I'm happy with v good quality basics that are not in fashion. I don't really follow trends, just wear quite classic things and tweak here and there as styles change.
So I suppose it depends whether you'd wear it for several years and make the cost per wear worthwhile. It's an unusual colour and might be hard to sell on if you get tired of it.
Re the drying flat instructions: I dry them on a microfibre towel laid over the flat bit of a clothes horse or over the pulley.