Currently BOTH is being used - peer review is the first pass, reproduction the second. Peer review might (or might not) weed out a few papers before they ever

Currently BOTH is being used - peer review is the first pass, reproduction the second. Peer review might (or might not) weed out a few papers before they ever get to being reproduced - and that a paper "passed" peer review often means very little. (In some journals more, in some less). You can't replace peer review with peer replication. Reviewers often do volunteer work - supporting their field and the journal by checking submissions just for any grave errors/mistakes. They often spend just 10 to 15 minutes per submission - for hundreds of submissions. It's not realistic to ask those reviewers to do a full replication attempt for hundreds of submissions. So any attempt to "replace" review with replication, would end up basically removing review altogether, without increasing the amount of replication attempts being made.