the only problem i see with the lifepo´s is,
that they usually only have 4-4.5 Ah (the acids / agm have 12 Ah)
and if you have to use the starter longer times, the lifepo stops earlier than the old acid´s and so on
caused by the lower Ah´s.
or if you leave the accu connected inside the bike, even the little on-board-clock will weaken the accu over 4-5 months very close to zero power.
and much faster this will happen if you got an alarm mounted and leave the system armed.
ok you can get lifepo´s with higher Ah´s, e.g. 8Ah, but then they get so very expensive ........
my comparison is based on our german prices :
the 4-4.5 Ah is available up from 65 €
the 8 Ah is always over 185-200 €
BUT
the starter motor whines / whimpers for mercy,
when you press the starter button.
even the "small" 4-4.5 AH lifepo4 delivers so much starting current.
it is always again a pleasure.
so i would recommend allways the lifepo4 for its usual use.