you don't have to buy and throw it away kung ayaw mo, try to deal with the shop if he's going to let you test the product, but of course the unwritten part is talagang bibili ka na, on one of the choices that he offered.
Or try to attend sep 20 dieselclub fun run, para makita mo rin setup ng ibang trooper doon.
jackaroo,
try to bring to any servitek shops, I have read some posts wayback in kotse.com days on dirty tricks some of the tire shops practice.