Most efficient FMIC

[Mistaspakles]

Anyone know what the most efficient FMIC out there is? Isn't a top to bottom flow FMIC more efficient than a side to side flow FMIC? I'm looking for a new FMIC like the one pictured. RRE has this with an 18x6x2.75. However, I'm looking for one that's 24x8x2.75. RRE sells this core but not with the endtanks. Anyone know where I can get this FMIC with the size I'm looking for with the exact style endtanks like the one pictured?

 

[Antilles]

Side to side has better cooling efficiency, where top to bottom have less pressure drop. then it depends on the type of core you use. a Spearco (bar and plate) is more resistant to heatsoak, but less efficient than a Griffin (tube and fin).