cooler question

I am looking to get into all grain some time soon, I have a few batches of extract under my belt and want to buy more toys! I will be slowly buying the turkey fryer, bigger pot, (i have an 8 gallon keg that needs the top cut off) coolers for mash tun etc.

My question is which coolers work the best, I know there was a previous thread a bout a square 48 qt, and doing 5 gallons you may not get great efficiency because of the grain bed being spread out. So are like the 7 gallon drinking cooler (like the gatorade ones) the best for a mash tun, and can always be upgraded to HLT if I get another pot?
I am probably sticking to 5 gallon brews for a while unless I can find a really cheap keg to convert to a keggle, but just wondering cooler wise what is the best shape to get, round drinking coolers, long square ones, or those taller square ones? Those taller square ones I think someone had a pic on here that they used to put a carboy in.
Last night I was reading somewhere to (cant remember where) that the igloo brand round drinking coolers didnt hold heat at all, so I guess I am looking for name brand and best size and shape

10-gal round Gott or Igloo coolers will probably give you the most versatility...you can fly or batch sparge, the grain bed's not too shallow on smaller batches, and you can do big 5-galon or small-medium 10-gallon batches in them.

They hold heat just fine...I typically lose 0-1 F over a 60-minute mash.

You can usually pick up one of the Igloos at Home Depot for $40

for spargin I see that, but are they better all around because of the higher grain bed?

What about the taller square coolers, anyone ever use those

I have a 48qt rectangle cooler...works fine. Others have reported using the "cube" ones with the wheels, also work fine.

If you are batch sparging, I don't think the height of the grain bed is all that important. You just want enough there to act as a filter.

I batch sparge in a 12.5 gal Ice Cube, and I have never even come CLOSE to filling it on a 5 gal. batch. Filter bed has not been a problem at all.