Depending on your goals and film all methods have benefits and drawbacks. I've worked on drum scanners in the past so my standards are high.
For B&W the dSLR + macro has given me by far the best results. My 24MP Canon SL3 provides the best balance of resolution and quality of scan. Grain at 6k x 4k it tack sharp and lacks the synthetic look of linear sampled plustek scans which are unfortunately all over the place based on quality of unit to unit. I've seen really good plustek scans, and crappy ones, likely depending on varainces in production. dSLR scans also lack the brutal grain definition of drum scans and don't have the annoying noise floor of Nikon units
In fact, I was discussing this on various reddit analog forums, and my dSLR scans with 100mm Maro with 400 Kentemere is capable of outresolving *ANY* full frame Canon lens I've used under perhaps 85mm - period. Also, converting monochrome dSLR scans is stupid simple using the invert curve trick of any free image software, Reddit Analog forum has a lot of amazing examples of B&W analog work that is flat out next level. They all use dSLR scanning.
Unfortunately I've found scanning rigs not as easy as they seem. I orignally started out with a piece of white plexi and a tripod, but this was a pain in the ass. First, I'm using a pretty heavy Bogen 3021 pod that's designed for much larger gear, and even with that my SL3 has enough mirror slap during 'scans' to cause sharpness issues. I have to brace the lens against my tripod to eliminate this. I could probably help this by getting a lens tripod mount, or a heavier duty ball head, but just mounting your camera and 100mm Macro on a tripod isn't that simple. You also need to be perfectly level or one side of the image frame will have soft grain while the other is sharp. You can spend hours aligning this, but if you move anything you have to start over. This is why most serious dSLR scanning is done with copy rigs. Much more rigid and less screwing around,
The tube based dSLR kits work good in concept, but have other issues. I bought the JCC kit mentioned above, and while it's well made it has other problems. First, it doesn't have enough extension tubes to get a a full frame with my 100mm macro even though it says it does. Next, the JCC film holders crop into 35mm frames just a bit. I don't need to see sprocket holes, but I don't want my film frame cropped even the slightest. If you are using a shorter macro and don't mind a tiny bit of frame cropping the JCC works fine.
When you switch to color neg or slide scanning you've opened up another gate. While color neg conversion works in Photoshop, it demnds a lot of manual work, which is why 3rd party software add ons are so popular. This is the big advantage Noritsu and Frontier scanning has in that these profiles are built in.
Certainly that was how lab prints worked. When I’m scanning 35mm I’m always more interested in having a 3:2 image than in capturing the whole image with the camera identification tangs and all the other paraphernalia.
