Refresh Ohm Walsh 4s or Walsh 5000 upgrade?

My Walsh 4s have been perfect for my space, with two REL T5s adding just a tad to tighten the base.  One crossover has finally gone after 30-40 years.  I am choosing between sending the crossovers and cans for a refreshing, or springing for the 4-5000 upgrade.  I read on the recent Ohm Walsh thread a few members have the 5000s.  Has anyone gone from an older Ohm Walsh 4 to the 5000, or had both?  What was the improvement or difference?

thanks