Having two B&M mega coasters in the same park does seem like an odd choice, but aside from differences in the ride experience, I think there are a couple of other things to take into account:
1) They are at opposite ends of the park, so it’s unlikely that you’d ride one straight after riding the other.
2) They have insane throughputs. Each coaster runs three trains with 9 rows of 4. Each train takes 36 riders, and by the time you’ve done a circuit, 108 people have been on the ride. I think the theoretical throughput is 1,600 an hour, and although I doubt the actual throughput’s that high, it can’t be far off. These B&M mega coasters do have epic throughputs. There’s no waiting for seats to tip back or floors to drop. There’s not belts to do up (for some reason some B&M mega coasters have had seatbelts retrospectively fitted and I can imagine this must be quite a hindrance on the throughputs). You sit down, pull down a bar, and you’re ready to go. It’s hard to think of other coasters that achieve this level of throughput without either having multiple tracks or duel stations side by side. There are a few. I think the B&M dive machines achieve this. The 30 seater trains like Sheikra and Griffin probably surpass it. But very few.
Throughputs are important at any park, but Canada’s Wonderland gets more visitors than any other regional park in North America. It gets more visitors than Cedar Point, Great Adventure, Great America… and although it has a lot of roller coasters, things like a wild mouse and a boomerang aren’t exactly people movers. Considering that visitor numbers probably go above 60,000 on a peak day (Canada’s Wonderland has a more compressed season than most British or European parks) they needed something that can really shift the crowds. That last statistic is based on what I was told at guest services, and may not be entirely accurate.
Incidentally, I’ve always felt it was a massive shame that Thorpe Park didn’t build a B&M junior hyper coaster instead of Stealth. Imagine if Thorpe Park had a roller coaster that could move the queues as fast as that. I know one British park did work on plans for a B&M hyper coaster, but that’s a different story.