Pierre Gasly has conceded testing Pirelli's new tyre construction for next season skewed his judgement of the differences between the AlphaTauri and Alpine cars.
The Frenchman will end his career-long association with Red Bull at the turn of the year with a switch to the Enstone and Viry-based outfit.
AlphaTauri experienced its best season in F1 in 2021 but its AT03 struggled to match its predecessor, finishing ninth in the constructors' standings behind Haas.
Alpine, meanwhile, beat McLaren to fourth in the championship courtesy of Fernando Alonso and Gasly's new team-mate Esteban Ocon.
Gasly took to the track behind the wheel of the A522 at the post-season Abu Dhabi test but could not make a direct comparison as he was given the Pirelli prototype tyres for the duration of the running.
Asked how that skewed his appreciation of the differences between his old and new machinery, Gasly said: "It is always a question mark because I did the whole day with this new tyre.
"From what we heard, it is not a big difference and also from my feeling, it doesn't feel like the tyre is behaving very differently to what we have had all season.
"So there is a question mark but overall, what I care about is what I can do with the car and so far it is giving me what I expected.
"There are obviously areas to improve and room for improvements but the car... I wasn't surprised, I knew it would be a fast car but I can definitely feel it."
Gasly in "transition phase"
Gasly was effectively loaned to Alpine to complete the day of running, which allowed him to integrate into the team and begin to organise working practices with engineers and mechanics.
But revealing he is now in a state of limbo between the two teams, Gasly conceded: "I am in a transition phase, let's say.
"Sporting-wise, I am fully focused for next year with Alpine but I still have a few commitments with AlphaTauri, but I will start working with the guys for next season."