B isn't the way to go, unless those old 50W don't work well. test them.
If they are Ok, then either A,
or C: get 100-150W panel and wire in parallel to those 2*50W.
150W is so little, almost nothing.
You might want to read
This on panel wiring.
On the quality: I prefer paying more upfront and getting parts that will work well and will last a long time. I'm also trying to avoid buying things that I can do without, no matter how good deal.
With controllers you get what you pay for. With panels - not really. I don't see anything particularly wrong with those 150W in your link (though would prefer them Polycrystalline). 5-7 years ago Mono were more efficient than Poly, but today Poly works better in most scenarios. The price is reasonable for 12V panels. High voltage / high wattage panels cost 2-3 times less per watt.
