I installed both of these on my CR-Z. Pretty simple to do. Just prep and clean area well before applying. And also don't rush it... take your time. I decided to add these since I already had a Clear Bra put on as well... figured I'd try to protect anything I could on the car... Plus you won't even notice these are on unless right up close.
As far as detailing... washing and or waxing shouldn't be a problem. Both of these items when installed correctly adhere well and will last quite a long time.
Yeah, you may want to watch it at those low temperatures!... If I remember correctly the instructions said to install it above certain temperatures so that the adhesive can cure properly... I want to say 60F or so... could have been 40F...? But I also remember the instructions stating to allow something like 48 hours before washing or applying any pressure to them. It's probably best around this time of the year to do it inside a garage or some place warmer and let it sit for awhile.