The rimrock is very nice. I know a few people who have stayed and loved it. It is right in the center or Banff.
Calgary can be very hit or miss for weather in July. We have had rain and cold (jacket weather) for the first week sometimes and other years its warm the whole month. Remember the mountains get much cooler at night if you are out that way so bring a sweater. Being so close to them we have on occasion received *gasp* snow in July and August!!!! Don't worry this isn't normal and it doesn't stay. Very interesting to see though
The whole area is great. I grew up in YYZ and moved here 3 years ago after visiting one to many times for business. My boss wouldn't let me relocate so I quit and got another job.
The real benefit is that you get the exchange rate in your favour. Its around $1.42 to a US $ today. Not too shabby.