If you're a Rogers customer, and you're happy with the coverage, you're not necessarily stuck paying Rogers prices. Several smaller telcos use the Rogers Network, so you can get the same coverage, but often at a lower price.
If your unlocked phone is from Rogers or is a GSM-standard 'global phone', you can bring it to a network powered by either Rogers, Telus or Bell.
If you haven't unlocked your Rogers phone yet, check out this guide on how exactly you do it...