for me its the 6's, i think the look is better and more professional. also the lil rubber tip on the 7's turns me off a lil since it goes under the toe a lil im afraid im going to lean forward stick and fall.
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Yeah... I'm a lefty...

I am not a big fan of dexter's but I would go with the sst 7s over the 6s.  in my opinion the 7s seem to hold up better than the 6s.  I had a pair of the 6s and they only lasted about a 1 year.  I ended up having to glue the pad and heel to the shoe because the velcro wore out on them.  I personally like the little plastic piece that the 7s have on them cause it looks like it will protect the tip of the slide pad.  On the 6s the first place the wore out of the pad was at the tip.  I had several times I went down the lane cause my slide pad rolled up under the shoe and I tripped and least with the plastic piece it will protect you from that. Had the same problems with the sst 5s also.  In a 4 year period I went through 3 pairs of Dexters.  Personally I would look at the Dynorooz shoes as well.  They are very reliable.  I have tour ultras and absolutely love them.  Anyways hopes this helps

Alan