Continuous Open Bidding (COB):(Sometimes known as COR, Continuous Open Recruitment) a time other than formal rush during which bids may be extended and accepted for eligible chapters. Some Panhellenic-affiliated chapters continue to recruit and pledge women throughout the school year.
Informal or Open Recruitment: a recruitment period conducted at various times during the year.
At Texas Tech there is no spring recruitment--only formal recruitment. I think it depends on your campus as to whether it is less formal, more laid-back or better. In informal recruitment you will probably have fewer houses from which to choose. But, again, it depends on your campus.