Points positifs : Staff was friendly in Lyon. Car was clean.
Points négatifs : Horrendous signage and location information at Gare Perrache, Lyon, and at Paris/CDG/Roissy.
In Lyon: "Dollar/Thrifty" location is opposite side of train station as all other rental car signage and information. No station employees knew where it was, partly because ONLY external signage was HERTZ, and actual office area is under construction and down an elevator nex to two broken escalators (which we went up and down two separate times with heavy bags). Searched and searched and searched for Dollar/Thrifty logo sign, since that was the operator on our reservation. Took us an extra hour to find the Hertz location after a random train station employee finally told us where. The Google maps pin for the address provided simply points to the geographic center of the train station, ie, completely useless.
This led us to be an hour late to drop off at Charles du Gaulle airport terminal 2E/F, arriving at 12:05AM, five minutes after closing. HORRIBLE signage at car return/dropoff because NO indication of any after-hours dropoff. Phone number for the booth did not pick up despite calling four times during our drive from Lyon. Did not see any info on our booking page about after-hours. Ran around in a panic in almost-deserted parking lot, finally a security/cleaning worker showed us the after hours drop off box. A hand-drawn sign on CARDBOARD is all that you'd need at the dropoff location next to the Hertz/Dollar/Thrifty booth.
So to sum: pickup was an hour of frustration and anger which led to us being late, leading to an hour of panic at CDG airport to drop off the car in a deserted lot. Unlikely that I'll ever book Hertz/Dollar/Thrifty abroad again due to poor communication and signage issues.
Oh and the car engine knocked under any acceleration which was loud and annoying the whole trip.