I live in Revelstoke. Selkirk Tangiers is a good option. They have a massive tenure (1/2 million acres i think) and have been doing it a long time. Plus convenient being right from the resorts base. Competitive prices too. I prefer cat skiing. Just as much vert, wayyy cheaper, and always seems a little more close knit and ready to rip-n-shred vs heli which seems to include more sightseeing, longer breaker, and often mellower terrain.
Mustang is one of the best cat ski operators out there. I'd like to get a group together for the Steep Chutes program sometime but it's expensive. They have incredible terrain and a ton of snow (almost all them do). Some of the other better ones include Great Northern, Retallack, Chatter Creek, Monashee Powder, Selkirk Wilderness. Many other really good ones such as Valhalla, Island Lake. K3, Red, RMR, probably not quite as good. My personal recommendation is Valhalla. I've been to a few and Valhalla has the best shredding-to-cost ratio.
Whether you choose cat or heli, most operators don't do single day trips (although a few of them do). Many have 3-5-7 days packages.
Try to get a 2-day trip. This way you save a bit, and being that you don't need to re-do your beacon training the second day, you get a couple more runs
If you can get a large enough group together, try to rent the complete snowcat/helicopter. Same abilities, the right terrain, super fun, cheaper. This is the ticket. No matter which you choose you will have a blast I will guarantee that!
When are you going? Often there are "shoulder season rates" (generally before Jan.15 and after Mar.15) If you are lucky enough to snag a day just on the outside of those dates then you are SET! Think 2nd week of Jan & 3rd week of March as the two best cat-heli skiing weeks of the season IMO.