For a Savage to be truly collectible, you need to try to find one that is correct...ie all Savage marked parts. All the parts save screws, springs, small parts etc. were Savage marked with the squared Savage "S" either alone or in a box....
A plain jane, been through refurb 3 times mixmaster Savage shouldn't bring much of a premium over any other No.4...
Find one that is all correct, or at least mostly (You can always find the needed parts somewhere), and its a definite keeper.
Sights are the same as on any No.4 Enfield...Either the micrometer adjustable Mk I "Singer" sight, the Mk II "L" flip sight, or the Mk III stamped adjustable ladder sight. It all depends on which sight you find on your gun. For shooting the Mk I sight is by far superior to the others...you can always buy a Mk I sight for your gun, but if it came with a different Savage marked sight, DO NOT TOSS the original, if you ever sell it, you'll want to replace the original sight on it.
As for shootability...I've never fired a decent No. 4 that wasn't accurate! I love Enfields, always seem to be dead on for me.
Long Branches (Canadians) are exceptionally nice too, very well and carefully manufactured, a far cry from the standard mid-war Brit No. 4...they still shoot great, but Britain wasn't worried much about cosmetics in '43-'44!
The nicest guns I have seen cosmetically and wood wise were always Long Branches!
Good luck, you can't go wrong with an Enfield!