There is evidence that it applies to big decisions too, although there's a tradeoff between satisfaction and success on objective criteria. One of the studies in that genre involved graduating college students choosing a job. The main independent variable was the personality variable of maximizing vs. satisfacing, rather than choice set size, but the results had a similar pattern. Maximizers tended to consider more possible jobs, get a job that was better on objective criteria like salary, and be less satisfied with their job.

Iyengar, Sheena S., Rachel F. Elwork, and Barry Schwartz (2006), “Doing Better But Feeling Worse: Looking for the ‘Best’ Job Undermines Satisfaction,” Psychological Science, 17 (2), 143–50. pdf

Expanding upon Simon's (1955) seminal theory, this investigation compared the choice-making strategies of maximizers and satisficers, finding that maximizing tendencies, although positively correlated with objectively better decision outcomes, are also associated with more negative subjective evaluations of these decision outcomes. Specifically in the fall of their final year in school, students were administered a scale that measured maximizing tendencies and were than followed over the course of the year as they searched for jobs. Students with high maximizing tendencies secured jobs with 20 per cent higher starting salaries than did students with low maximizing tendencies. However, maximizers were less satisfied that satisficers with the jobs they obtained, and experienced more negative affect throughout the job-search process. These effects were mediated by maximizers' greater reliance on external sources of information and their fixation on realized and unrealized options during the search and selection process.