Unless you want to start off the way you will (probably) end up diving, and
that is with a nice simple backplate and wing (the best system IMNSHO), then
the Syncro 840 is a good standard BCD, always assuming it's in good
condition.

It does not have stupid bits like integrated weights, self adjusting
'powered' cylinder bands or any other useless fitments, however it is
comfortable, strong , decent size pockets   and has sufficient lift for all
UK single cylinder diving.

This was made in the days before Mares started down the fashion and
marketing bandwagon of putting on as many bits with three letter acronyms as
possible, and just concentrated on making quality, rugged and well designed
kit.

I had one for a few years when I returned to diving about eight years ago,
my wife also had the very similar Syncro Platinum.

If your buying second-hand then give it a full check over.  Fully inflate it
and make sure that all the buttons on the inflator work smoothly and  that
it does not lose pressure, even when left for an hour.   Make sure all the
dumps and over pressure valves work OK, including the pull down one within
the corrugated inflator hose and the rear 'bum' dump.

Mares fitted one of the best inflators on this model, both comfortable to
use and reliable, but with age even this can become tired and could need a
service.

If all is well then its probably worth between £100 to £150 S/H as they were
about £275 new price.

Hope that helps.

Brilliant BC - mine finally gave up the ghost after about 8 years of use :-(

The only thing to sat is that this model hasn't been 'New' for many years
now, so a second hand one needs to be checked out as previous post. If it is
in good nick then it would make a great 1st BC.

Regards
Kevin