Big fan of bottomless portafilters, mainly for ease of cleaning and how damn nice the coffee looks when coming out of it. Also pretty handy for diagnosing issues with tamping. Probably won't lead to a discernable difference in taste, unless the spouts on your old portafilter were pretty disgusting.
The portafilter from my Gaggia Classic broke so I have ordered your a naked bottomless one.
Quite interested to see the difference when it arrives.