Used this one for few years up to age 12. Big enough to lie in www.argos.co.uk/product/3650921?cmpid=GS001&_$ja=tsid:59156|acid:444-797-0832|cid:189934165|agid:18091993285|tid:aud-264064232575:pla-101860333765|crid:77627768365|nw:g|rnd:6426246789736821210|dvc:m|adp:1o12|mt:|loc:9045957&gclid=EAIaIQobChMItrjD8t3I2gIVC40bCh3FNQyhEAQYDCABEgLT7PD_BwE}
cestlavielife we have the same one. It's great and still gets used every year. My daughter is 11 and plays in it whenever the weather is good enough. We had a cheap plastic slide that she (and sometimes her older brothers) used to slide down into it.
But what they really wanted at that age was something like this...
We got one of the 10ft round ones. You fill it once and ours came with a pump and filter, and then you need chlorine and stuff. Ours had hours of fun in it last year with assorted inflatables and it had just gone back up this year. We had one with a slide a couple of times but they both punctured so we went for a plain one.
Can I just ask a q about the 10ft round ones? Do they have to stand on a perfectly level lawn/patio? Our lawn is really uneven and we don’t have enough patio for it. Otherwise I really like the idea of them.
Ours is on a slight slope and it is fine. It has to be quite flat as, the one we have at least, maintains its structure best when it is full up so if you have one side with not enough water, it will be a bit wobbly. Probably depends how uneven? It kills your grass anyway, so could you try and level it out with top soil for the area you want to put it?