Sales and Distribution Certification - questions

Dear all,

I am a SD consultant with 5 years of experience through all the SD processes although I have never been certified.

I am going to take the certification but I have several doubts which one is appropriate to me:

1 - I see 4 certifications for SD - 3 at associate level and 1 at professional level. I don't know anyone who has taken the professional one. Do you recommend to take the professional?

2 - The 3 certifications at associate level cover similar areas: TSCM62_64; TSCM62_05 and TSCM62_60. Which one is more appropriate to a SD consultant?

3 - I know that the certifications expire after a while. Do you know what is the validity period of a SAP certification?

Thanks in advance for your help.