On the one hand, the 56x series were very good processors and the 565 should be an inexpensive way in, assuming you accept that these units are of an age they might fail and therefore need your soldering iron skills! The 568v2 was the best of these, but don't forget the 561.

On the other hand, the 861v2 is similar in terms of upgrade options (as in not really upgradable), but was the pinnacle of Meridian's achievement at around the same time, so would be very tempting. It's possibly more repairable too as it was built as a modular unit and the cards are swappable.

I can't speak to the Gxx series as I was on a Meridian sabbatical at the time and went from the 5xx to the 8xx series (and haven't looked back)!

Prolific music listener / Hi-Fi addict!