Well, I've had the Sure Fire for a little over a month now.
I'm a low speed (16-18 mph off my hand) with about 250-300 rpms and 19 degrees of axis tilt. My PAP is 4 1/2" over, 1" up. I drilled up a Sure Fire as follows:
-1 1/2 inch pin
-~2.5 oz. of top weight
-Pin 4 3/4 in. from PAP over the bridge
-CG rolled out slightly (about 4 1/2 in. from PAP)
-Small hole drilled on the VAL a little below my PAP
As you can see, I drilled it for a more skid-flippy reaction, and I will say that this ball shows absolutely no quit on the backend. I love the reaction, but I do have to be careful when I'm playing straight because it can jump high. It does squirt a bit on oil, but that is the drill and not the cover at all. A great ball, and it is versatile, but for me, on the hook side of versatile.
I would say that it is a great idea to start an arsenal, but for you, I would probably use a more controlled drill on it. Probably something like 4.5 pin-pap under the bridge, CG 4 in. from pap and a medium hole put in around the midline-VAL intersection. This should keep it very consistent on the backend and make sure it won't squirt at all. I'd probably then use a similar drill on the Spit Fire. However, I would use a higher pin (over your bridge, and in a slightly weaker position) and try to keep the CG near the center, then only add a weight hole if needed. I think that should give you a lot of different looks with the two balls and keep them from being condition specific.
Just my random musings, feel free to take it with a grain of salt.