Both series are sweet reality dating shows with the participants living in the same house and interacting while doing missions. In the end they would choose the partner that they like. The only difference is that in Love timing, the participants are non-celebs and there is a panel that discusss the interactions. While in Idol and Romantic, korean idols are the participants.
Both have strangers who are non-celebs that cohabitate in one house and they date while doing missions. Both are reality shows with panels discussing the interactions of the non-celeb participants. Though Love catcher has an added spice since not everyone is in it for love... some for money. So the panel and participants have to guess, which makes the show more interesting.