In the four that I have in rotation, the one 2600 performs no differently than the three 2800s.

Ken

Any setting changes needed other than the charger?

None  The 2600 has enough "head room", the 2800 has more.  I don't make any changes to the charger either.
On my charger a LiIon will charge just fine using the Lipo setting.  I get a slightly smaller charge before it stops but is well over what I need.  Makes it simpler when you have both.

Ken

Ken, OP was asking the difference between 2600mah Li-ion and 2800mah Lipos.  You are comparing 2 Li-ion batteries.

As usual you are exactly right.  The answer is similar.  The LiIon will "sag" a bit sooner than a Lipo but they can be run down considerably more than the Lipo and the timer makes them pretty equal.  The Lipo should be > 20% "head room" where as the LiIon will probably be < 10%.

Ken