[Thimothy]

I don't know if you have ever been to Gibraltar, but I have friends who have worked there, and the line that separates it from Spain is (always have been) really porous. If customs are implemented again it will just going back to the really good old days of smuggling.

[mcorrand]

I have no doubt things will keep chugging along, but the time and energy wasted through customs for the commuter working in Spain would be a major pain.

[blablablame]

I worked there. The lines sometimes took hours. Saw cars dismantled trying to find drugs/tobbaco. I left after 5 months as I couldn't stand the border anymore. Sure, if you need a visa, things will be harder, but really doubt the queues will be much worse since Spanish border control most of the days are spiteful as hell