Solar Panels Brands - does it matter?

CA Traveler wrote:

2x270W = 540W, 45 MPPT, $832 and 35 sq ft
6x140W = 840W, 60 PWM, $1035 and 64 sq ft
3x270W = 810W, 60 MPPT, $1034 and 53 sq ft

Yes. Now imagine that you have 64 sq.ft total space available that breaks into several small areas so you can't put 3x270W. So you have to go with either 2x270W or 6x140W, and the latter will result in more watts. This what I've been trying to tell - the shape of available space may dictate the choice of panel size. 6*140W will also have a lower per watt cost than 2*270W. Just an example...

The panels for a given setup all need to be closely matches unless multiple controllers are used

Yes. The OP should better get all the panels at the same time, rather than "upgrading" later. In the past the panels cost $6 per watt and people could not afford enough wattage, so they were buying one panel, then another, and it was mismatched, and the efficiency was lower. But now panels are cheap, 10 times cheaper.

JiminDenver wrote:
Wow do I like that 270w panel. It's the same size as my 220w mono and at least 10 lb lighter.

I would be wary of panels too light, especially with relatively new brands. There can be a lighter aluminum frame or thinner glass. Though 37 lbs is not "too light", it's more like a "normal". My (pretty old brand) 245W Poly weighs 39 lbs, and all their panels from 220W to 250W have the same size and weight. I guess with higher wattage panels they just leave smaller margins between the cells and around the perimeter.

Some panels have a flimsy frame with single-wall vertical side, while others have a double-walled side. The material is usually thin, less than 1/16", so the frame profile does matter.