[g__day (Matthew)]

For a 10" OTA I'd be thinking the EQ8 around $4.5K is a decent option, add good quality mounting bars ($200 - $400), an Off axis guider ($250) guide camera ($500) a modded DSLR ($600) and a decent PC controlled focuser ($550) and you're at around $7K to carry that size tube.

The cheaper option is to go a faster 4" refractor + good focuser (say $3K - there's a Williams Optics FLT 110 Triplet + Moonlight focusers on the for sale pages that meets this spec) + and eq6 $2K + cameras and once again you are scraping up towards $6.4K. But this option allows you to sell your old OTA or now have two.

So it depends if you want deep field shots or wide field, which may depend on your quality of night skies and what you like imaging. The fast refractors are alot easier to get results from than a larger Newt or SCT.