the very limited experience I have in this regard was with Ansprechpartner - SFSC - Swiss Finance Service Center after they did some general finance seminars through ETH. I perceived them as quite professional and knowledgeable, although we were not talking about pension planning at this time. They do offer that.
The one thing that made me walk away was that they systematically pushed 3rd pillar life insurance products to academic personell (PhDs, PostDocs, Students) through this channel. One of those cases is described in detail here. People from that target group very likely leave the country after a few years, so these (already borderline scam products) are especially bad for them.
When confronted about this, they became extremely defensive, and we never interacted again.
The “Lehrmeinung” says you should look for an advisor paid by the hour, but i have yet to find one that won’t converge to selling stuff.