Exchange or keep depends on a couple of things.
(have edited this a couple of times while it's pending moderator approval, sorry if this is all repeated comments that others have posted in the meantime).
The Trend 2 is a polished hybrid, it's a pretty aggressive piece and none of the exchange offerings are really the same.
Cost is a consideration too, especially since it sounds like your Trend 2 is undrilled. The Storm exchange is not free, you have to pay for shipping and if the ball is undrilled, you won't get a drilling voucher back. So, it's going to cost you out of pocket $30-50 to ship it plus the cost have the exchange ball drilled. Plus 1-2 months to actually get the exchange ball back from Storm.
As others have pointed out, the events you plan to bowl in are a big consideration. The Trend 2 is disallowed in USBC national tournaments but likely will be allowed in many local events and leagues. Check into that locally though, as others have also noted any local leagues and tournaments have the option of adopting the national USBC exclusion rule too - some are and some are not.
If it were me, I'd keep it and enjoy bowling with a free high end ball (other than the tournament entry fee and hard work to win it). But, I am terrible and not bowling in anything where it would be excluded though.
If it were either of my kids who are actually good, they'd exchange it right away because they bowl Jr. Gold events where that ball isn't allowed. My younger one tried a friend's Trend 2 around Christmas and loved it. He has been saving up for his own Trend 2 but dropped it off his want list as soon as the exclusion announcement came out.
For what it's worth, all of my kids bowling friends (teenagers) are aware of the exclusion situation and are already calling those 6 balls using "cheater" balls whenever they see one, regardless of whether they are actually allowed in particular events or league. Anyone with a thick skin should be able to ignore that, but I'm sure lots of people are experiencing similar comments in other leagues and events right now. Some league officials have a tendency to cave under pressure from vocal league members.
My 16-year old sent back a month-old Electrify to Storm to exchange it for a Gem, he's pretty excited about that, but actually a little disappointed to lose the Electrify.
The Nova is a monster too. But, other than price those are all pretty different balls than the Trend 2.