Just a heads up on the Samyang/Rokinon/Wallimex etc branded lenses. I have been watching the auction site to buy some.
The new current prices of the VDSLR lenses with focus grip is higher (because of the higher construction costs) than the "Pro" branded versions which offer conventional focus grips. While the "pro" version apertures are marked in f numbers, the VDSLR lenses have T numbers.
On the auction site (.de specifically), the VDSLR lenses go for much less than the "Pro" versions. It looks like the higher T numbers put people off.
I grabbed a 14mm T3.1 VDSLR lens recently (great price). Size wise, it isn't going to be a lot bigger than my Canon 50/0.95 lens in M mount. Any Distagon (old, new or even upcoming- any mount) ~15mm FL is by no means a small lens!
The 14 f/2.8 (or the 14 T3.1) lens is already shown to be a great performer on the A7R.