I'd be very interested in a scanner that:
1) uses a CMOS or other high quality full frame (rather than line) sensor;
2) employs optics that are truly optimized for flat field performance at the magnifications required for the variety of different magnifications mandated by by a variety of different film formats;
3) includes a reliable, consistent output light source (like electronic flash) that provides continuous spectrum light of appropriate colour temperature;
4) includes filtration for the light source to match the light to the design specifications of the mask in C-41 negative materials;
5) provides useful, flexible and efficient provisions for handling sheet film, complete rolls, and short strips of roll film and mounted slides, in a manner that ensures film flatness;
6) includes provisions that prevent interference from ambient light, and help remove/minimize/eliminate dust;
6) includes software protocols that are exactly matched to the sensor and light sources employed - both for positive and negative films - and provides file output that suits commonly used image editing software - not just Adobe products; and
7) is small and attractive enough to have out in open view.
In order for the optics to be of high enough quality, I accept the fact that it may be necessary to have multiple lenses on a turret or sliding mount.
In order to maintain the consistency of light output and sensor response, it may be necessary to include calibration hardware and software.
Do you think it would bee more than $300.00

?