Got an FR301 as well. Still on the first tip. Whenever I had it clog up all the time I cleaned the tip with the small cleaner, cleaned the metal pipe between the tip and the glass chamber with the bigger (screwdriver like) tool, cleaned the glass chamber and rubber seals (had to replace one of those already) and, most importantly, replaced the filter. The filter has only limited capacity to take up dirt, once it's filled air won't pass it well enough to create sufficient suction at the tip.
The FR301 is great, only downsides are that it's heavier than a desoldering station's iron and that you are physically closer to the place where the smoke gets released. I wear an FFP2 mask whenever I use the desoldering gun now.