I haven't tried many REN products but the ones I have tried I've liked.
A while ago I bought a little starter kit which had 4 mini products in and one of them was this pore minimising detox mask.
This product was thick. Really thick. It felt like I was plastering my face! This little 15ml tube was enough for one quite generous application. I left this on my face for about 15 minutes until it felt like it had adequately dried.
Once washed off my skin was left feeling soft but I wouldn't say my pores were minimised. I suppose with a few uses it might start to have an effect but there simply wasn't enough product in this tube for more than one application.
As I said I've had my sample for quite a while and I now think this has changed name to the invisible pores detox mask and a 50ml tube is priced at £18 and available from REN online.