Rapid fire at level 5 hits 8 times with a base damage of 204. at rank one, it seems like a 50% chance of hitting 7 or 8 times. I would assume at rank 10, it hits 9 times (or possibly 10).
Multi shot deals about 160 damage per hit for me, while Rapid Fire does about 255. A full rotation of MS R5 is about 12 hits (50% more than rapid fire), making MS deal roughly the same damage as rapid fire, with a 9 second shorter cooldown. The only difference in RFās favor is, Rapid Fire has a higher base damage, which means against bosses less of that damage is mitigated.
Ultimately think of it as a second Multi Shot of equal rank, with Rapid Fire being a slightly better for bosses since higher damage and stationary for less time.
these damage numbers are with 68 strength, 18 dexterity. switching to 18 strength, 60 dexterity seems to lower the damage by about 50 per hit.
Unrelatedly, Iāve found out that SP regenerates one uptick every 20 seconds, and Oblique shot can be used 8 times in 10 seconds. That means with an SP recovery of 160, Oblique shot rank 1 wonāt even cost you mana. I have no idea if thatās worth it though.