GPRS data is cheap in the UK - so it isn't expensive everywhere in Europe.
My Swiss SIM is with Swisscom, although to be honest that was primarily out of expediency. Swisscom and Sunrise seem to have the best coverage.
Any Swiss provider accompanied with a callback service would be a good option for calls to the US. The orangeclick.ch option might be good if you will have heavy calling to make up for the monthly fee.
As for data, I didn't use much due to the cost. 2.50 CHF a megabyte isn't horrific but it still isn't exactly inexpensive.
CA: SaskTel, Wind postpaid; Rogers, Bell postpaid iPad flex plans; US: T-Mobile postpaid data, prepaid voice; PureTalk (AT&T MVNO) prepaid voice/data; AT&T prepaid iPad plan
Hardware: Too much but notably iPhone 5, iPad Mini Retina LTE, Moto G LTE (N.A. version), iPhone 4. All unlocked.