Transiting PTY is very easy no secondary checks or anything, problem is, the airport has like no concessions, only a cheap hotdog stand.

has good prices on electronics, somewhat similar to US prices, but considerably cheaper than neighboring countries such as Colombia and Venezuela.

LAN's supposedly a very, very nice airline (FTR, I never flown them) so why not give each one a try on the first two legs and then decide what you like best and suits you?