Based on quality alone, Broja should prevail but the others are more experienced in English senior footy so the temptation is there for Southampton to stick with them.
I don't think they will just sit him on the bench all the time,they pay him after all. in the end small clubs know most quality players will not stay for long no matter if they are loaned or bought. they have to survive and if that requires playing a loanee they will do it. Some might still appreciate the player as Wigan did with Reece if the quality is just too much to ignore or try to sway him like everton with lukaku.
The problem with loans is, if the loanplayer is just ok-ish he will be scrutinized more critically and play less than he deserves