HELP - 100W 12V vs 175W 24V solar panel - HELP

[inetdog]

Some low end MPPT controller cost around $50 for 10A or $90 for 20A (no display) that is what I'm planning to buy. Will it has the same performance as premium one which cost $200-$300? what it the different beside LCD display?

Unless it is a name brand, such as one sold at our host, the fact that it mentions MPPT in the sales stuff is no guarantee that it really is MPPT or that it does a good job if it is MPPT. The display is not important to functioning, but since it tells you what the device is doing, it makes it hard to lie about whether it is MPPT or not.
It is also handy if you do not have a clamp-on DC ammeter to check the system with.

[Beanyboy57]

OK, OK, OK

Base on my current equipment (100W/12v panel; 175W/24V panel; charge controller; 1 battery 60AH); how many watt and hours I can use off from solar and battery output?

In your first posting you say you have a 600AH battery? Which is correct?