Probably, the ים של שלמה was the greatest intellectual endeavor in Jewish history; meaning: what he tried to do was kind of more courageous than any book in Jewish history. He wanted to review all halakhic literature up to the year 1550 – that’s what he wanted to do. No one’s ever tried to do anything like that, but, sometimes, we say in English, “you bite off more than you can chew.” He bit off more than he could chew and, therefore, מהרש”ל is interesting to study, historically; practically, he’s not really relevant.
Rabbi Adam Mintz, “The Battles Of The Polish Rabbis Regarding The Methods Of Codification”, RabbiMintz.com (31 January 2012) {http://www.rabbimintz.com/audio/the-battles-of-the-polish-rabbis-regarding-the-methods-of-codification/}