finally pulled the trigger

[scarletboa]

i finally broke down and bought a MMM esc. i was planning on buying another ezrun 150a esc, but i like the idea of actually having a good warranty. i paid $170 for it at my LHS. i know i could have gotten it for $150 shipped off ebay, but i prefer to support my LHS. it took me 5 months to get my money back from the burnt ezrun and the refund was from nitrorcx, not hobbywing. also, i would like to change my settings without making the esc catch fire

couple of questions:

i plan on running 6s on my savage and 4-6s on a CEN matrix buggy. how high is the failure rate on 6s? i will be using 25c 5000mah zippy flightmax 3s packs for the savage and buggy and 20c 2s 5000mah turnigy packs for the buggy.
both the savage and buggy will be geared for ~40mph. i don't think those setups will push the batteries or esc too hard, but i would like a 2nd opinion just to be sure. while the warranty is nice, i would prefer to not need it.

also, i bought just the esc separately instead of the combo. will it still come with castlelink?

edit: the matrix has a 60mm 2000kv medusa motor and the savage has a 1400kv KB12L motor.