Rogers and Fido are, in essense, the same. Rogers owns Fido and all the plans are practically identical.
Although, I would personally go with Rogers. (Not only because I work there) But there aren't nearly as many Fido stores as there are Rogers stores. So for me, i would prefer to go with the company which will offer the most customer support if needed. Therefore, go with Rogers.
The plans are the same (practically), and with Rogers you can change your plan anytime (with no penalty or fee) and that way, you can be sure you always have the best plan.
As for text messaging, Rogers offers 2500 texts/month for $10. Although, if you are only texting the same few people, you may want to get a my5 plan because you will have unlimited talking and texting to your 5 (for as little as $25/month).
As for service, Rogers has the better network. Although Rogers owns Fido, the network coverage is a bit different; I will explain. At first, Fido was it's own independant company and it put up their own GSM cell phone towers. A couple years later, Rogers bought Fido. So, when you subscribe to Fido, you are signing up with their GSM towers and there arent very many of them. Although, you DO have the option of paying $5 or $10/month to have access to the Rogers cell towers. If you subscribe to that, then the network coverage will be the same. But why pay extra when you can just go to Rogers?