Went rafting on the Rangitaiki with my cousin earlier this year with Wet'n'Wild - oh man what an experience!
I'd called a few days earlier, and the owner put together a trip for us. Two others signed on as well, so it was 4 of us total.
HUGE storm ripped through the area the day before we went, leaving trees all over the access roads! Long story short, there's a reason lumberjacks don't wear wetsuits.
Once we got the river, it was clear it was worth the effort. The trip rips off with Geoff's Joy, an extremely fun and certainly memorably grade 4 rapid. Lots of 3+ and 3 rapids to follow, covering some excellent scenery. Great river, would recommend the trip to anyone who's interested in rafting.