I'm looking to add 2 bowling balls to my hyper cell skid to make a total of a 4 ball arsenal (including my spare ball). What two options do you think would be best? I'm a tweener, with high tilt and about 45 degrees in rotation. Right now looking at the hyroad, uproar, wrecker, and the outcry.

edit: forgot there are the locos too

I know you don't have it listed, but I would look at the Haywire because you don't have a solid in your arsenal. Then either a Uproar, or the Outcry. Uproar is more skid flip where the Outcry will be smoother and pick up a little sooner. Also you might just want to check out the Devour (solid)  as well. I guess it depends on the lane conditions that you are seeing.

I think the Outcry is a better ball than he Uproar or Rumble.
Just based on observation of the 3 over the last 15 months.

The IQ Tour Nano is a favorite. Optimus Solid is pretty neat. The orig Hypercell is still legit and very strong, and would be a ball up from your Hypercell Skid. There still used on the PBA tour. Those new Roto grip balls are much stronger than last summers releases.

If your new to Roto grip, I wouldn't dive in head first, you may want to just get 1 or 2 first to make sure you like them. I had 6 of them, sold 4 of them in the last 8 months. Ended up liking the Storm gear more, more consistence for me.

I am the opposite. I matched up with Roto Grip vs Storm. So everyone is different. I would do your research. Then if you can, try to go to a matchmaker event (ball demo) so you can try different balls before you buy.

What is the main theme of why people like one side more than the other? Storm has skid flip and smooth stuff.

Marketing, driller on staff, or bowler determines their next ball based on how well he/she remembers throwing something from 6 years ago.

At least that is what my unscientific study shows.

I drilled up the haywire I preordered but when talking with my pro shop guy about a ball down. We landed on IQ tour solid, hyroad, unhinged, sky rocket, uproar, and wrecker. Now even more confused

Great choice on the Haywire. I absolutely love mine. With your last choice I would go with either the Uproar or the Sky Rocket. I have the Uproar, for me it is a skid flip type of roll that I can use up the boards, and it hits and drives strong, more angular. The Sky Rocket is new, but it is also a pearl . I am not sure if it is stronger than the Uproar.  I would research those 2 -- IMO.

THat Sky Rocket is a sweet piece, just used it on a modified sport 37' and shot 733 out of box. This shot was not easy, this ball when long and just finished, drilled pin up 5". Nice ball so far.. I like the Sky rocket better than the UProar, clean yet strong but controllable.

PBA challenge league - depending on the shot you may need a Hyper Cell --- for the benchmark I would do some research. I can only guess w/o seeing your shot. Possibly an Outcry?  I am not sure about the Skyrocket?