The deluxe Silers are product improved over the old Silers .
It appears anyway that the Siler kits from Track are basically the older Silers with the older shorter throw cocks . The old locks needed assembly by someone who knew the tricks of tuning and getting the balance between the mainspring and the frizzed spring right .Getting the frizzen to trip over also needed some monkeying with the toe of the frizzen. Some builders also changed the pitch of the cock so the flints wouldn't get smashed. I had one assembled that smashed flints in about ten strikes.Absolutely frustrating
A tuned older Siler was and is a good lock if assembled by someone WHO knew what they were doing , it had a less travel needed to get the cock to the frizzen, but requires a shorter length flint .
All in all if I were buying a lock I would use the deluxe if I had to choose between the two unless you luck into finding an older siler which was actually assembled correctly at a bargain price . (I inherited an one that had been used as a freestanding demo lock , never installed on a gun that I used on a build recently and this one goes off quick and doesn't smash the flints. Had in not worked I would have replaced it with a Deluxe WHICH I checked on mine and would have dropped in with a little beveling on the lock plate , that was plan ''B''.)
All that being said there are locks I like better now as time and experience has produced a plethora of decent locks in the last 15 years .My current favorite is Chambers early Ketland , it has a pleasing shape ,the tail does a much better job of following the wrist so it be blends in better , and it's big and sparky .And it works for most colonial builds unless you really want that germanic influence .
Since I'm more interested in a good shooter to take to the local matches I'll look at the lock first when considering a build then the barrel and it's handing weight then ergonomics then find something that matches those parameters historically so I don't look like a doofus carrying around some bad mix of parts . I would rather have the best barrel and lock that I could afford in a simple gun .
Of late I've been shooting a barn gun inspired by the late Don Getz's work ...wood patch box no buttplate no entry thimble or muzzle cap on a Beck profiled stock . Mike Compton down in Iowa actually assembled it for me as I was moving at the time. He did a fabulous job selectively darkening the stock, antiquing it .Like Mike Brooks said recently buttplates are overrated .
Sorry I wondered off topic too much time on my hands this morning .