For reference, I've both boosted and leveled regularly with RAF to 60:

Leveling 5 at once: 0-60 in 2 days, 4 hours /played

Boosting 4 toons with a 70: 0-60 in 16 hours, 2 minutes /played
Details of my boosting:
1-15: Boosted other 4 with my 70 hunter for run speed boost (questing)
16-20: Stockades boosting with my 70 pally
20-45: SM Cath with my 70 pally (tried ZF, Temple, SM was still way faster from 40-45)
45-59.98: Strat undead side with my 70 pally
59.98 - 60.98: granted one level from 2 of my 4 boostees (after dinging them 60 seperately) to the other two

The boosted toons are still at 60 with no skills trained past level 10, no mounts, and no riding skill.