Good afternoon,
I fully "grok" the refurb route but....... I couldn't work out which Jamis you had and a post search didn't help, but it did turn up one where you were considering a touring bike to fit between the Jamis and the Specialized Diverge.
This suggests that you have quite clear requirements for your equipment and as any CF framed bike sold around 2012-2014 would generally be quite highly spec'd I wonder if you will be disappointed by doing a refurb.
Apart from possibly going from 10 to 12 speed, as far as I am aware there have been no big changes in mechanical group sets. So you would be spending your money on getting back to where you were, I am very comfortable with 10 speed and expect to be forced to 12 in the near future (Di2) but I have no desire for 12 speed.
The exception would be if the Jamis has disc brakes, this would open up the option of 105 Di2, the price is horrendous, typically around the £1,400 mark plus the cost having it fitted and the cost of making Di2 work with a cable based frame. So it may be cheaper to buy a new 105 Di2 bike.
But I absolutely adore Di2, for me it is a much bigger improvement than going from a 531 to CF frame and as controversial point I suspect that many people don't like admitting that they can't afford it so they rubbish it.
As I commute a bit under 40 miles a day I decided that I would use my best bike, a CF Jamis with Di2 and recently bought a new steel frame and built up a "retro" bike. The retro bike is way worse than the Jamis in every way, but I really enjoy riding it because I approach the ride knowing that this is as things once were.
I have spent around £1,200 on the Raleigh, it has new frame, wheels, shifters, saddle, seat pin, bb, bars and stem and from my spare parts bin front and rear mechs, brake levers and chainset. I would like to replace the drive train when I find the right bits and expect to end up at around £1,500.
So my question is would a complete change of direction and a step back in absolute performance actually give you more fun?
Bye
Ian