The 150w panels Renogy is selling have only been available a few months now. They didn't have them when I bought my 100w panels. I would expect them to be made to the same quality level.
Here are the links to the specifications for their new 150w panel.
http://renogy.com/wp-content/uploads/2014/05/RNG-150D-Datasheet-01.jpghttp://renogy.com/wp-content/uploads/2014/05/RNG-150D-Datasheet-02.jpgThese panels already have MC4 connectors on them which makes cabling easy.
If you are going parallel you can buy a pair of MC4 Branch Y Connectors (MMF and FFM) and that will let you easily go from two panels to your extension cable. You shouldn't need too long of extension cable. Buy one cable twice as long as you need and cut it in half to make your extension cables.
If you want to go serial and your panels are next to each other you won't need the Branch Connectors.
