I’ve played with both 50k's and 70k's. 50K’s are much more stiff in the ankle. Price is also a bargain. 250€ in Finland for eg. 70K’s are lighter I admit. Though they feel almost the same than Super Tacks or FT1. Memory foams don’t stand a chance against the pump! I know, I’ve tried! But it's up to you. 🙂