No, not a huge factor.
Hi @ab490, welcome to solar, Australia, and the forum 
Those quotes do present a tough choice. They are all very good prices though on the face. Quote 2 probably offers the best gear, with the SunPower panels, but I’d lean toward quote 3 as best overall just based on price and products.
Cheap for a reason is definitely something you have to be wary of. I think the best advice I can give is do a lot of research on the companies, and choose based on that. The products and price are important, but given they are comparable, it’s the quality of the installation and service that is really the main thing here.
Hope that helps
Cheers
Marty