When purchasing solar powered pumps you need to be sure that you fully informed of what they can and cannot do and we will try to outline the pros and cons for you.
OPTION TO CONSIDER:
First - if you require the pump to run 24hrs a day 7 days a week - DO NOT BUY A SOLAR PUMP
Second - if you are happy for the pump to only work during sunlight hours and with fluctuation due to cloud cover or not to work if overcast then a Solar panel and pump set up is for you.
Third - if you require your pump to be able to work during cloudy periods or evenings for a limited time (1 - 6 hours depending of your battery back up system) and you are willing to turn the system on and off then the Solar pump with panel and back battery is worth considering.