1. I think everybody have the same dilemma. nobody knew how to differentiate between one tint to the other (me included). Just to be on the safe side, get the branded one and ask for any paper warranty. Just in case anything happen, at least you can claim the warranty.
2. To be fair to both party, if the dealer agree to cover the cost of RM1K for the tint, why don't you add to your liking. I mean rather than he tell you that he's installing RM5K tint in fact he installing rubbish bag to your udm.
3. why don't you ask this dealer what he can offer (normally accessories) and compare with other dealer. This things (accessories) can be bargain.
my 2 kupang