Attention Topaz Photo AI users. Does Topaz work for...

I have been scanning old family photos, slides, and negatives for several years. Recently I picked up a Plustek negative scanner and it does a fantastic job, so good that the film grain is very visible. I have been looking at picking up the Topaz Photo AI suite but before dishing out $200, I was wondering if anyone has used this on scanned photos, slides, or negatives. What I'm wondering is:
1. Does Topaz handle film grain like noise? I've tried using Adobe's noise processing but it does not do much even when I put the slider at 100
2. Does Topaz work with .tif and .dng files? All my scans are either tif or dng. Unfortunately, Adobe's Denoise doesn't seem to work with these files.
3. Any real life experience would be appreciated especially with scanned photos/negatives/ and slides..

I posted two samples below that show the problem well. The fils is Kodacolor CII from the early 80's. The main image was under exposed so it shows grain clearly. Also, they are %200 screen shots so the grain is clearly visable.
The first image - Left side was scanned with an Epson V600 and VueScan and the right side scanned with PlusTek and also VueScan with the same parameters.

The second image is scanned with the PlusTec with the left image with no noise reduction and the right image with Luminance turned up to 100, Detail up to 50 and color up to 50. It's a bit better but still real grainy.

I've been wondering about this myself, but I never got around to playing with it.

I ran this image, a scanned 8x10 print from Tri-X pushed 2 stops to ISO 1600 (probably) through Photo AI.

I left things on autopilot and it sent me to the 'Upscale' portion of the app. I'd never been in there before. It looks like there's some noise suppression and sharping in there. Here's a screenshot from the app. Stuff to the left of the white line is unprocessed, to the right, fixed.

I'd have to play with it a little more, figure out what that upscale thing does. But the results look promising.

WOW!! More than promising, that looks significant, way more than I can do in PS by itself. Thanx. Would be interested in any other samples if you try any others.