Hi @Vramos
“Top Tier” is not a brand, it’s a generic term for basically anything.
Read this chapter in our guide first:
https://forum.cleanenergyreviews.info/t/ch-6-what-panel-and-inverter-brands-should-i-buy/159
And also this chapter:
https://forum.cleanenergyreviews.info/t/ch-2-who-should-i-buy-solar-from/155
Cheers
Marty