It's perfectly valid to scan burns from burner A with burner B. Just don't compare PIE/PIF scans from burner A with scans from burner B (but your Sony can't scan, so basically that's of no concern to you).
The burns made with your Sony don't look good at all, however I would recommend to also perform a transfer test of the burns (preferably with both drives). Maybe they aren't as bad as they look.
Regarding your burns with the NEC 3540, I would say the first one is very good, though PIE is a little high at the end. Nothing to worry about though. The single high PIF spike can be ignored. The second burn looks less good, there is a cluster of PIFs in the 0.6-0.7 region which I don't like and the PIF tops 300 near the end, though by my standards this isn't a bad burn either.