I have never sent a gun off to be refinished by a pro so I have no advice there. However I have put on DuraCoat finishes on a few guns and have found it to be very durable. You can buy the kit with everything you need for about $50. This includes the cleanser, airbrush, air supply, finish, hardener and reducer. There are several different colors to choose from and it is really easy to do. I did a DuraCoat finish to my Sigma last year and it has held up great. I don't carry the Sigma but I use it as my project gun and often sit with it at night while watching TV and push it in and out of a holster to test the finish. I even dropped it the other night and it did not even mark the finish. So far I am very happy with it. Here is a couple of pics of the two guns I have with the DuraCoat finish, the Sigma and my Polish p64. As you can see down on the front of the slide of the p64 there is a spot where the finish chipped off. This is where I did not get the slide prepped good, so as you can see prep is very important.

I love hard chrome - makes the slide holsterwear proof pretty much. Hardest fiish you can get.

I like the matte hard chrome - but they can do it shiney as well (brushed)

Who does Your hard chrome, & what is the approximate cost ?

Thanks,-Jim

Here are two reputable refinishers and both have experience with Sigs.

http://www.ccr-refinishing.com/

http://www.robarguns.com/

Robar's claim to fame is the NP3 coating. I don;t know what Brad at CCR uses, but all the info is there on his site.

You can also send the gun to Sig to redo the Nitron if you like.

I've not done this yet, but will send one Sig P226St back to Sig to Nitron the Slide for a two tone effect.