To this point I haven't needed a narrower filter for the TS-480. From past experience, I wouldn't buy the Kenwood filters, but would go with the INRAD filters instead, world of difference. I also wouldn't use a filter as narrow as that 1.8 one. I've found that cascading two 2.1 filters sounds much better to me, less distortion. That's a 'personal' thingy, so listen to that 1.8 before getting one.
I also have found that I don't need a TCXO for the '480 ... yet. I wouldn't mind having that option, but haven't needed it so far.
The one option I'd really like to have (don't sell them in the USA) is the doo-kicky for combining the radio and control head. Of course, if I really had to have one I'd just make the silly thing. Oh well.
- 'Doc