heat welded seems to last longer than stitched...
Vinyl vs. mesh sees to be personal preference...
vinyl seems to protect better from water splashing from below while mesh drains the puddles better. Raw nees you can get on both.
My heat welded vinyl style tramp made it for 20 years. Replacing the rope on an aged tramp should not cause trouble. Check for squareness while you are at it re-lacing the tramp. Patrick