The new model Knosti MKII + is a vast improvement over the original model in the red box, the rinsing kit is what I recommended to many people over the years its a no brainer.
For 300 LP's no sense wasting money on a Pro-Ject machine IMO.
The best RCM fluid is called The Right One (based on the fact I have used every RCM fluid known to man over the last 30 years (MoFi/Monks/Moth/L'art du son/etc etc)
Many people make up their own, I would rather get it right as I treasure my vinyl collection and these home brew mixtures never seem quite right to me.
Knosti's own fluid does a good job also.
CS Port TAT2 - Benz LPS - Funkfirm Houdini - DS Audio Vinyl Ionizer - CS Port C3EQ - Kondo G70 - Kondo Gakuoh II - Maxonic TW1100 MKII - Isol-8 SubStation Integra