Depends on the rep and the corresponding gen. If I saw a gen sub in decent order for 4k I’d jump at it. There are reps with many gen parts and are sometimes worth it, but I agree they can start to encroach on the lower end of the gen pre-owned price ladder. I don’t think there is any hard and fast rule that you can apply to this question but I personally would be reluctant to part with thousands of dollars or GBP for a rep, regardless of how many gen bits it had – but that’s just me.