Backstay with sheave and 7x9 wire OK?

[catd]

Hi all. Just wanted an opinion, or two. We recently replaced all our standing rigging excluding the backstay. Then we noticed a crack in one of the swage fittings on it and decided we should replace it too. Our current configuration is 1x19 wire at the mast head running about 2/3 the way down, it then attaches to an aluminum sheave which has 7x9 wire running through it to each side. Our rigger didn't like that set up with the sheave (too much pressure on it he said). He recommended all 1x19 starting at the masthead, spitting near the top of the mast and then running down to turnbuckles on each side.
Well, we actually like the way it's set up now with the backstay adjuster on the 7x9 because it's really easy to adjust. We don't really want to change the setup, however ,if it really is a weak point in the system (as our rigger said) then we'd switch.
Hope I gave enough info here. Thanks for any opinions, thoughts...
Catherine