I have had some of my best luck with:
On Ya Kneez - DJ Unk (nice bass scare drop)
All Black - Plies (cool sweep)
You ain't know - Sean Paul of Youngbloodz (another good "suprise" drop)
Oxycotton - Lil Wyte (an old favorite)
Bring it back - DJ Unk
Houston Oilers - Mike Jones
Go to Work - Kay L (don't know how i found it, ish hits!)
Let My Beat Pound - TI (name says enough)
Boi I Got So Many - Young Problems
Juicebox - Gorilla Zoe (LOOOOOOWWWWWWWSSSSSS galore)
Throw It Up - Lil Jon (MUST HAVE WITH SUBS)
Lost - Gorilla Zoe
Back Da eff Back - Dj Paul
Hood Dreamer - Willie Northpole (great song in general)
Dat Baby Don't Look Like Me - Shawty Putt (funny, and it hits!)
Hoods Run Down - Lil Wyte (sweet test in the beginning)
Blueberry Yum Yum - Ludacris (get it)
I wanna eff you - Snoop Dogg (don't plan on hearing much with the bass turned up, nasty!)
White Girl - Young Jeezy (sweet bass)
On Fire - Young Dro (mixtape bass, different type of Dro)
Love for Money - Willie the Kid (sweet drops, goes low)
Slow Motion - Cold Flamez
PUT ON - YOUNG JEEZY (somewhat overplayed anymore, never gets old to me, all-time favorite basslines...)
And to switch it up a bit, try some Mama i'm Coming Home by Ozzy.
Are any of these a waste of "purchase'?! Absolutely not.