Fisher retainer worth it?

[Roth_Trailfinder]

There are some useful fish out there. It's your call, TC, whether or not to level Fishing so you can get them yourself. Once you have leveled Fishing however, then the question changes. Do you want to spend the time fishing the useful things, or do you want to let your retainer get those useful things that it can get, so you can spend that time doing something else?

[Lissandra]

I have one but only to get me fish... Which isn't all that often.

[Nekotee]

Got 3 fat car and 1 gestahl out of mine plus one stack of each fish need for ALC solvant
And I also think that my Fisher got the best rng for random one hour mission
Because he is the one that give me the best item out of my 5 retainers

Funny things...
Whenever i send my mi'qote botanist and my aora Fisher both in 1 hour venture
The Fisher being back wood or fruit... The botanist give me fish

Suspicious...

[Werhusky]

I have a FSH and a BTN retainer. The FSH turns out more useful as I get the fish for Caviar enough to keep a stack in our FC chest and i can get some convenient fishes with him.... the BTN is meh besides getting Floss Silk. Atm I have the feel the gatherer retainers aren't really worth but changes may come... maybe.

[Mithrahn]

My 60 FSH retainer(s) [well, two actually out of 8 retainers] are my most useful.
My 60 BOT retainer(s) [also two out of eight] are my most useless, constantly can't find what to have them bring back so i just send them on long ventures, already too much Birch Logs and Birch Saps and the other mats, I don't even really need.

I just send both of my FSH retainers to get Hinterlands Perch for me every venture cause my CUL's Desynthesis level is at 199.22 at time of this writing.
It's constant supply of Quickarm Materia IV or Allagan Gold Piece with the occasional Yellow Pigment or Fine Sand (the last two of course I don't care much for)
Not to forget the guaranteed Water Crystals, so even if you get fine sand, at least your water crystal supply will still go up.
After amassing enough Quickarm Materia IV, I usually just bring all of them to Mutamix and mutate all of them for a chance to get Grade V materias.
Managed to get (notable mentions) quite a few Competence IV's, and a couple of Quicktongue V, Competence V and Guerdon V from mass-mutamixing of Grade IV's.
Or, well, if you feel it's a waste to gamble for good materia by mutating 5 into 1, you could always sell those Quickarm Materia.

Long story short: FSH retainer is actually a hidden Grade IV (and if lucky through mutamix-ing, Grade V) materia farmer when combined with a CUL that decently levelled his/her desynthesis levels.