Although I don't have a top 5 since all of their songs are perfect, but I do have a top 25 most played on my iPhone.
1. OVER DRIVE
2. Koe
3. KOSHI - TANTAN
4. Anata ga Mawaru
5. Orange juice
6. DOLL
7. Hoshi no furu yoru ni
1. OVER DRIVE
2. Koe
3. KOSHI - TANTAN
4. Anata ga Mawaru
5. Orange juice
6. DOLL
7. Hoshi no furu yoru ni
8. Sparkling
9. Taiyou Scandalous
10. Shunkan Sentimental
11. Kagen no Tsuki
12. Rock'n Roll
13. Hello!Hello!
14. Kagerou
15. Weather report
16. Welcome home
17. Rising Star
18. S.L Magic
19. LOVE SURVIVE
20. FUTURE
21. Aitai
22. Secret base ~Kimi ga Kureta Mono~
23. Koi no Gestalt Houkai
24. Cute!
25. Bitter Chocolate
Additional 26. Runners high
And many more! The list will continue to change as SCANDAL continues to play awesome songs like they always do!