You've hit the nail on the head here; half the PSV forums would happily take £20m for Strootman. The other half aren't so sure though.
Those who would take the cash for him, they don't want to see him leave because they think he's a poor player; the simple fact is that £20m is a very large sum to pay for anybody in the Eredivisie, especially so a defensive midfielder. PSV could buy a whole new defense with that money, and many believe that, however good Strootman has been for them, they sorely need three or four new players and that if his sale would fund that then it's the right direction to go in.
Others seem to believe that the club would be getting something of a raw deal at that price though. The £12m sale of Vertonghen last year from Ajax to Spurs in his final year of contract seems to be a benchmark oft cited; they see Strootman as a player of far more value than Vertonghen, and the PSV captain has three years to run before he can leave for free. Some believe £23-28m then would be an attainable figure in this case.
Then there are those who believe the club should hold onto Strootman until next summer, by which time he'll have competed in the 2014 World Cup finals in Brazil. It's generally accepted that the player's recent run of poor form is little more than a blip in the development of a genuine star of Dutch football; many see him doing very well at the next major international tournament, by which point any fee commanded will exceed that being talked about at the current time.
As previously stated then, Strootman is neatly dividing opinion all over. It's certainly not unusual for a player to divide opinion on a football forum though; take a look at our very own Manchester United forum for examples of pretty much every one of our players dividing opinion. The impression from the PSV forums is that Strootman is clearly very talented and valuable to them, but that £20m would nevertheless be very difficult to turn down for any player in the Eredivisie. Some believe the club should snatch United's hands off if such an offer were made, whilst others are urging caution, believing that they might be selling themselves somewhat short in the circumstances. They seem resigned to his leaving the club and have been for quite a while; the leading cause of debate now is 'At what time, how much for, and who are his replacements?'