Set up a fair contest, not a forced switch
Cats reject most litter changes for reasons that have nothing to do with the litter: the tray moved, the hood appeared, the depth changed, and the new product got blamed for the whole disruption. A two-tray trial strips all of that away. Place a second tray as close as possible to the existing one, matched in size and style, filled with the new litter to roughly the same depth your cat is used to digging in. Fill the familiar tray exactly as you always do. From that moment, freeze every other variable for the trial period: same feeding times, same cleaning rhythm, same room layout. Whatever preference emerges is then genuinely about texture, scent, and feel under her paws.
Run both trays on an identical cleaning rhythm
Scoop both trays at the same times, morning and evening at minimum, and top both up the same way, because a cat who chooses the old tray on a day when the new one sat dirty has voted for cleanliness, not against your new litter. Keep visiting guests, new furniture, and other household experiments out of these two weeks if you can.
Record the vote properly, including the split verdicts
Preference is more detailed than which tray is emptier. Note each day which tray received urine, which received solids, and whether anything landed outside a tray altogether, because cats commonly split their vote: many will urinate happily in a new texture but return to the familiar tray for solids, where they dig longer and feel more exposed. Watch the behaviour around the trays too. A cat who sniffs the new litter, shakes a paw after stepping in, perches on the rim instead of standing in it, or scratches the floor beside the tray instead of burying is telling you the feel or smell bothers her even if she sometimes uses it. A cat who starts choosing the new tray for everything within the first few days, and buries calmly without paw-shaking, has given you about as clear an answer as cats ever give.
Read the result at the end of the fortnight
Judge the trial on the second week more than the first, since novelty itself attracts some cats for two or three days before the true preference settles. A clear win for the new litter looks like consistent use for both urine and solids, relaxed digging and burying, and no deposits elsewhere in the home. A clear loss looks like avoidance, rim-perching, or any toileting outside the trays, and that answer should be accepted without a second attempt to persuade her; with litter, the cat's comfort outranks the owner's preference for a cheaper, flushable, or better-smelling product. A split verdict points to a compromise some households keep permanently, running both litters in both trays or keeping the old litter for her main tray. If the new litter wins, retire the old tray's contents gradually over a few days rather than swapping overnight, so the victory never becomes a sudden change of its own.
Keep the household reading from the same tally
A trial collapses when one person scoops helpfully and reports nothing, leaving the tally full of gaps that get filled by guesswork. Put the daily notes where everyone who cleans a tray can add to them, with the same simple marks for urine, solids, and accidents, and let one person sum up the fortnight before any bags of litter are bought in bulk. Recording that running tally in KinsLe Care Teams, alongside the twice-daily scooping duties themselves, keeps the experiment honest from the first day to the decision at the end.