At the moment I am contemplating road bike rental options and what personal cycling accessories to bring on a trip next week (leaving Friday).

The rental options are:
Cervelo R3 105 - $250
Cervelo S5 Rival - $250
Trek Madone 4.7 - $300

Given that I ride a Caad10 Rival, I would like to stay with the same group, but the S5 geometry might be too different. Which bike should I pick if I want it to be familiar?

I plan to bring:
Shoes
Multitool
Clothing (including gloves/sunglasses)

I do not plan to bring:
Pedals (should be provided, but not guaranteed)
Saddle
Helmet

What do you recommend I bring with? Any advice is appreciated since I've never rented a bike before. Thanks!