Worktop Or Spacer? - Tile Advice

[GDJTAM]

In the process of tiling my kitchen walls between below my kitchen units and the worktop. I was going to start tiling with the tile resting on the worktop and working up to the unit. However, a chap and keen DIYer told me to sit the tile on a 2mm spacers to allow the bead of silicone to seal beneath the tile.

Is this the best way or just sit the first row of tiles on the worktop and then run a bead of silicone?

 

[J Sid]

spacer

 

[CJ]

Spacer or wedges

 

[White Room]

All to the above...