I've had a few meetings with schools around my area. I've flown the R22 a bit and liked it but there is a school within line of sight from me that operates the 300C. So I booked myself a flight to see if I like it more. (it's also about 40 an hr more expensive than the 22)
40 an hour difference probably isn't significant - a good instructor can save you that by getting your license sooner. Check with the existing students to see what they think of the school. Get a feeling for how professional the training is, and how experienced the instructors are. Go with the school with the better staff, rather than blindly getting the cheapest rate. Ask around a bit about the schools reputation before you make a final choice.
And never, ever, give any school more money than you are willing to lose if they suddenly go out of business. At least here in the States, it happens all the time
