Shimano Claris vs 105?
I've never used Claris, but I've used a bunch of different Shimano road stuff, from 8 to 11 speed, as well as some SRAM.

All other things being equal (which they never are), the more expensive Shimano groupset shifts smoother than the less expensive one. That, however, is splitting some really fine hairs. The shifting performance for modern brifters is nice across the board. In my experience, what makes a groupset good is how well you adjust and maintain it.

I vote for the Claris group. 8 speed is still widely supported and will probably remain so--you are unlikely to have a problem finding replacement parts (which are also much cheaper than 9, 10, and 11 speed parts) before you trash the whole groupset. 16 gears is also a pretty good range for any kind of riding.