3x rollover is great for a 100% bonus. So now let me clue you in on something that will blow your mind: the Bonus Game.
You invest, say, $1,000 at Bookmaker and decline any bonus they may offer so you have the freedom to withdraw when you want. You invest $1,000 at SBG and have $2,000 in your account with the 100% bonus. Here's where it gets ingenious: you bet both sides of the same game on the ML, trying to win the game at Bookmaker, and lose at SBG. You bet the amount you expect to win on the favorite as your risk on the underdog.
e.g. New England Patriots are -500 against the New York Jets at +400. So you bet, say, $100 on the Patriots to win $20 profit. You bet $20 on the Jets even though you expect them to lose. This way you protect yourself in case of an upset. But the goal is to win, win, win at Bookmaker and lose, lose, lose at SBG. Do that enough and you've moved your SBG account from $2k to zero. But you've transferred that $2k (or thereabouts because there will be upsets and even though you're betting both sides, there is vig) over to Bookmaker. You now have $3k in your Bookmaker account, can withdraw it right away because there was zero rollover, and you made a cool $1k.