The free stuff I've tried is rather poor. Even iZotope RX (it has a free download, if that counts) which is superior to SF NR in many ways has, I think, a rather poor pop and click remover. I just tried it this evening on twenty hours of tapes that had been transferred with slight tracking problems, which introduces a "static like crackle." Both SF NR and iZotope were able to reduce or eliminate it, but I could not find settings in iZotope which didn't introduce all sorts of thumps and gargling. This is a problem with any click remover if you turn up the controls too much, but in my past usage of this feature in iZotope, it always seems to have this problem.

However, if we move onto the next part of restoring vinyl which is the background hiss and rumble, iZotope's NR is MUCH better than what SF has to offer.

In both cases, when restoring vinyl, less is more. There is always initially the temptation to remove every last bit of noise and every last click. If you do this, you almost always end up doing violence to the original material, and it sounds closeted and unnatural.

The Forge pop and click removal will remove most of the offending stuff. However if you open the project in Forge and expand it to maximum on the timeline then highlight the small tiny offending area then delete it (cut) you can play it back and never know that a portion of the project was deleted. It is virtually undetectable by the standard human ear.
JJK

SF is good for all of the above, but a program that is specifically made for record restoration is the Diamond Cut software, such as DC6. It was used to restore many of the old Edison lateral recordings for the Smithsonian and the forensic version is used by the high tech investigative agencies. The non-forensic version is very reasonably priced, has an amazing Help section and will do the job. The latest version is DC7, I believe. It comes with hundreds of presets. One of my favorite features is the "virtual valve" section that creates the sound of tube type preamps using various tubes such as the 12AX7 and others.