Most newer balls are technilogical upgrades of balls that have already been released, much like all other sports equipment. The shells and weight blocks are constantly being tweaked for "better" performance. Some bowlers have a hard time replacing "old faithful", I've even got a couple that I refuse to retire. In the Easter Sr. High Roller in Vegas, in the last day of matchplay finals, we started with over 100 bowlers and I made it to the top 8,..only to get thrashed by a guy using a very old original urethane Blue Hammer. Not every new ball is a great ball for everyone, believe me, read some of the reviews.
Different conditions across the country, coupled with everyones individual variables makes pleasing all the people all the time almost impossible. As a ball company staff member, I have my favorites in our line,..and I have the ones that don't seem to work as well for me,...but another bowler my have the opposite opinion,..that's why there are so many to choose from. What I tell perspective buyers is "do your research",..find out the specs that best fit your game, and the drilling patterns you best like,..then talk to your pro shop guy for his opinion,....jim