Or am I making a big mistake???
Or may be the original X10 with the original sensor will become a cult camera with superior quality over its predecessor and its value will be untold!
For my two-penneth worth on the subject, I see it this way, bare with me.
I recently chose a Volvo V50 as a company car. I could have had anything within my budget. I considered BMW 320, Audi A3, Lexus IS200 and so on. Each had some good qualities; each had some negatives, like high P11D value, not enough boot space, MPG and so on.
I considered what the main use of the car would be, against what it would cost me and chose the V50. Why, it fits 90% of my use, long motorway cruises, going out with my family, economical ect. Sure if I went on a track day it would not be the best option available but do I do many track days, well no. Would I still do a trackday in the V50, hell yes.
My point is this, if you go looking for problems you will always find them and if you are after something for one specific task then chose the tool that best suits the task. If you are after a multi-tool to do all tasks then compromise is always inevitable.
If you want a good all round camera for everyday shooting is the X10 a good choice, well for my needs it suits 95% of what I want from it. If I was only going to shoot low light images with bright objects in the scene would I chose a X10, hell no. If I was in a situation were there was a good low light image with bright lights to be taken would I use the X10, well yes it will still be a good image but it may have some orbs that some people may find distracting. Thats my compromise but I can live with that.
The X10 does what I want to do with it today and it will still perform the same tomorrow, next year, next decade and so on. Ok better option may become avaible in the future but that is not an opion here and now.
Do I consider what the X10 will be worth
second hand, well everything is subject to deprecation and I would not say we are talking thousands here, so is it worth worrying about.