yup mate. 9300 would be 2 generations better than the 7100 and from the higher end product line. it also should hopefully come with a year or so warranty, i'd check the serial number.
its short comings is the HDR only has 2 tone curves whilst the Epson 9400 has liek 20 via HDR slider.
I dont think it has any shortcomings compared to the 7100 and should leave it in the dust with 4K e-shift, some HDR support out of the box, better contrast and black floor.
The new bulb is worth £100 alone and will ensure you get about 1000 hours of very high end bright performance from it.
I own 2 of them and I think they are fantastic machines for the money with a premium build quality, excellent lens shift, most have warranty coverage for at least a year even now, cheap as chips bulbs to replace and enough lumens to be usable in most setups.
Its major cons to watch out for are:
1. can't do 4K&60&HDR at the same time
2. no dynamic tone mapping
You didn't quote how much ur paying but if its in the region of £1000-1300, I think its an absolute no brainer this day in age. Its performance is VERY comparable in 2D/4K/3D to a 9400 which is FANTASTIC value now we have its successor released at £4500.
an upgrade from them would be the JVCs if you manage to see any in that price range. I don't think you'll find a comparable Sony projector at the 9300 price.