I thought I'd answer Laurie's question here because there may be others who are wondering the same thing. On the Magnolia website (Sweden) there is an option to buy the stamps either unmounted or EZ mounted. Both types are made of rubber and you need to use them with an acrylic block to be able to stamp. The difference between the two is that the EZ mounted come ready to use right away while the unmounted are just the bare rubber. In order to use the unmounted stamps with your acrylic blocks you either adhere them each time with double-sided tape or you buy your own sheet of EZ mount and mount them up yourself.
So, it really is up to you. I always buy the unmounted from Sweden. They are lower in price and I tend to buy quite a few at a time (I find them hard to resist). It is more cost effective for me to then buy a sheet of EZ mount and mount them myself but it does take a little time to do. I find I save money that way.
(When I bought them from Diana at Magnolia-licious they were already EZ mounted. It was a nice treat to be able to use them right away.)
So, I hope this helps you make a decision. If you need any more help, please just ask. I just started to stamp, so I may not have all the answers but I'm a good researcher and I'll be able to a least point you in the right direction.