"Go and get a feel" should surely be the "tie breaker" once you've done all your other due diligence and research on Unis, subjects, etc. You can't seriously think it should be a major deciding factor on it's own??
DS had done loads of research, lots of soul searching, etc., when trying to choose the uni/course. We went to several open days along the way, but honestly have to say that he pretty much felt the same way about them all, none stood out in particular, all much of a muchness, and most of the presentations/info etc he'd already seen on the Uni's own websites. Basically he thought they all just did the same and probably copied each other - same format of "presentations", most labs looked the same, similar range of clubs/societies, etc. He got very little out of them and they didn't help him choose.
In the end, he finally chose the degree subject, and then his "short list" was very short as few Unis did that exact course. Basically just 2 Unis did it in our half of the country. He'd been to an open day of one, but not the other. He got offers for both. One was RG so his initial thought was that was the one to firm. But he went to both offer holder days, saw the reality of "a real day" at Uni at each, not the sanitised open day, and decided the RG wasn't for him at all, so he went with the other.
So, for him, the only benefit of the "go and get a feel" was to put him off the one which was "better on paper"! So, yes, going and getting a feel was useful in the end, but it was way down his list of what he thought was important - what was far more important to him in both choice of Uni and course was the job prospects.
He wasn't going to waste 3 years of his life and get £50k in debt based on "go and get a feel" and risk not getting a good career at the end of it.