Original post by Pimped ButterflyLacazette would be better in the short term too. He has all the attributes to succeed in PL football, and is a better player than Benteke all round. And you don't make signings, not in the least £25m signings like Benteke and Lacazette, for the short term.
Liverpool signed Adam Lallana this summer (debatable whether he was a back up to, or the first choice ahead of, Xherdan Shaqiri) and injuries meant that we immediately lost the value of his 'PL readiness', ie there's no point putting value in the 'PL experience' myth, because moving from a smaller club to a bigger club is can be just as big a change in playing style as it is across leagues. If a foreign player doesn't immediately succeed, it can more often be put down to being played in the wrong system (eg Suarez under Dalglish) or to other factors like injury, playing in a losing team etc, rather than 'not being ready for PL football'.
Lacazette is a rapid, physical beast of a striker who's excellent on the counter. I see no reason why he would struggle to adapt to the quicker transitions of this league (actually he'd probably thrive, just as Torres, Aguero, Costa did).
So this PL experience thing is, as previously stated, a giant myth.