I would say no, just enjoy it as is.
Why would you need the extractor? Are you having extraction problems? It will do nothing for accuracy.
I got a MkIII Hunter a couple of months ago and decided I "needed" the VQ sear, trigger, and springs. So I have $50 worth of stuff that doesn't do much. My advice is to save your money.
The sear makes no appreciable difference. The spring it comes with is probably too light, and causes reset issues in my gun. Next time I have it apart I'm putting the stock sear spring back in.
The trigger is, as far as I can tell, useless. It has a pretravel adjustment, but if you try to adjust out the pretravel, the sear doesn't reset. The mechanism has a spring and plunger arrangement to maintain some slack in the trigger; You cannot adjust that out, so you're
always going to have pretravel in this design. Adding
any pretravel adjustment on the trigger of mine causes sear reset failure.
The stock trigger already has a formed-in lump on it to act as an overtravel stop (at least mine did). If you attempt to adjust in any extra overtravel stop with the VQ trigger, guess what? The sear won't release!
The one positive point with the trigger (or the whole "upgrade", from my perspective) is that the VQ trigger shoe is a tad wider than stock, and I like wide triggers. Oh, and the hole drilled in the face for the OT screw isn't as annoying to the fingertip as others I've shot.
My opinion is that Volquartzen made big bucks making 10/22 parts, and decided to expand into the pistols without putting a lot of thought into parts that were actual
improvements.
Don't waste your money on the titanium disconnector. I can't even imagine what that material is supposed to buy you in that application, other than relieve your wallet of excess cash.
If you're interested there are a number of threads over on
RimfireCentral.com discussing the VQ upgrades, including at least one with a masked expletive in the title, if that tells you anything...
Lastly, I
am very happy with the MkII bushing I put in my MkIII, thus eliminating the mag disconnect, and improving the trigger quite a bit. This obviously isn't a problem for the OP, however...
-- Sam