NAM wrotethere is no need .. Ogero provides the internet to all ISPs so Ogero has the best ping .. now luck plays a big role in where you live .. depending on how far the central is from your house and the condition of the wires.
To summarize i don't think there is any chance you could get better ping than from Ogero "from the ISPs mentioned" .. unless the neighborhood ISP has their own underground ways.
That is not totally accurate yes ogero is the main provider true but that doesn't mean what ogero gives the other isps is given to you.
Ping depends on where you live and how far from the central point you are most of isps use ogero central points but for example IDM had there own called gds. Do not forget where you live wich city affects it alot examples at dora tarranet ping google at 40ms (speed very unreliable)
Sodetel is great arround mansourieh area...
If you tell us where you live we can give you more accurate information.
Last thing check for the dsl packages and prices they vary A bit maybe that will help you choose.