Of course we need.As we know,love is a thing that is very uncertain.Even we don't know which kind of sensation is love or we are just like taht one.If a guy says that he/she loves you,don't trust him/her immediatelly.Test is certainly necessary.
How to test the guy is a big issue.But I think time can be a measure which is uesd to test a love.If somebody has loved you more than 5 years he must be love you.But it will kill your time,love isn't all things for you after all!