[avandonk]

The Starlightxpress SXV-M25C looks like a very nice alternative to mono CCD's. The only real advantage over a Canon 5DH is that the chip is cooled. It is fair to compare the two as they in the same price range. The Canon 5DH has a well capacity of 80,000 electrons compared with 25,000+ for the SXV-M25C. This means the 5DH has an inherently better signal to noise if you ignore the effect of cooling the chip in the SXV-M25C.
It would be interesting to do a comparison exposure of M45 with a comparitive optic. I will try with my Tal 200k (200mm dia) at F9 and see how it compares to 250mm diameter at F3. I will also see how the 5DH compares at 300mm focal length at F2.8.

I am of the firm opinion that any imaging system is better than none. All we individually then have to do is get the best out of it. Comparisons should only be made when thoughts of upgrading become seriously chronic.

It is coincidental that these were the two alternatives I considered when wanting to upgrade from my Canon 20D.

Bert