Help me decide which to use until I get Cell

I have an alt team that consist of androids just for fun and casual PvP. So far my core for this team is SP Blue Android #18 and SP Green Android #16 but Idk who to choose as my 3rd main since I don’t have SP Perfect Cell yet but I could use either SP Purple 17 or EX Yellow Cell Jr. which one will I benefit the most? Cell Jr. Z-boost androids tag and 17 only z-boost himself (Purple tags only) This site said that EX Cell Jr. have SP rarity stats and he is in the top tiers for EX Characters plus SP Android 17 is a tank which I am already using Android 16 as my main tank in this team.

Thanks in advance