Just to be a pedantic PITA (I know, me?!), but that wouldn't matter here as the SOGA would override any manufacturer warranty at this point. Really, they're pretty much useless as your contract is with the person who sold it to you, not who made it. If it's non-compatible, then you are due a refund.
But yes, I would only ever buy parts from a reputable dealer in this country: You only get bitten once to learn from that mistake.
I just think - Take this as an example.
Customer buys a stillen product from tarmac, issue with said product, customer rings tarmac wants refund/replacement. As tarmac is a licensed trader for said brand, he would I guess have a good relationship with said brand and will be able to contact them and arrange something.
Scenario B
Customer buys stillen product from Grundy's Gizmo's (Great name I know ) issue with said product, customer rings Grundy's Gizmo's wants refund/replacement. But because I'm not getting my stock straight from Stillen, and getting them from somewhere else and selling them cheap to get my sales in, I either now have to out of my own pocket give this guy a refund/replacement orrrrr just tell him to do one.
I think that makes sense anyway