We have nothing but good things to say about Profil Cuba-Reisen.
The 2 rental bikes and 4 panniers that you provided were of high quality. We rode them over 300 km (Holguin-Banes- Playa Moralez-Gibara-Holguin, including side trips) and in all that riding we had no problems at all (once a chain came off, which took 2 minutes to fix). The tires were top-of-the-line touring ones (Swabbe Marathon - highly resistant to punctures and suitable for paved or unpaved roads).
The bikes we're delivered to our casa particular in Holguin at the appointed time by 2 very nice gentlemen who carried them up the stairs, and then offered me a choice of 2 seat types. The seats were also of high quality. When we arrived back in Holguin a few hours earlier than expected we requested that our bikes be picked up that afternoon rather than the following morning, and this was done.
Also, when we were deciding whether to rent bikes we really appreciated that Profil Cuba-Reisen sets out on its website exactly what is offered and the prices. When I submitted additional questions, they were quick to answer them. We are grateful for the excellent service we received, and we highly recommend Profil Cuba-Reisen to others.