I've had a .177 Fortitude Gen 2 for a little over a year now and here are my thoughts and experience with it.
The length of pull (LOP) is very short and the butt plate is slick/slippery. I added a slip on recoil pad which extended the LOP and added some grip.
The trigger does need attention. All I did was to lightly polish the contact points and did the 2 screw modification. Trigger is still not good, but it is usable and I have found that I can get used to just about any trigger with enough time and practice.
Something not mentioned very often is that the shroud MUST be centered in the barrel band! The barrel/shroud is supposed to be free floating and NOT touching the barrel band.
However...
If you put much pressure on the stock at the end nearest the muzzle, the pressure tube WILL make contact with the shroud and cause POI shifts. Unfortunately, this makes attaching a bipod by using the sling mount at that end of the stock useless. This problem shows up mainly when using a rest or a bipod, but I don't think it will affect most off-hand shooters as they will probably not be supporting the rifle out that far on the stock. I always use a rest of some sort and have gotten used to putting the part of the stock where the main screw/pressure gauge is located on the rest and not the end of the stock near the muzzle. This solves the problem, but took a little getting used to.
I can't tell you how many shots I get per fill because I never let the gun get much below 2500psi/about 30 shots before I refill it with a hand pump. Usually between 30 and 35 pumps.
Luckily for me, mine shoots the CPUM 10.5 pellets at 1 MOA or less out to 40-45 yards. Back when I had access to shoot out to 60 yards, it did just as well. Never tried it farther than 60 yards. I can't tell you how far I have my hammer spring turned in, but I shoot the CPUM 10.5 pellets @ ~755fps for ~12-13fpe at the muzzle.
The regulator on mine seems to work well, but I can't give you a spread sheet on the extreme spread. Last time I checked I think ES was around 15 or 20 fps and SD was probably about 5-7 fps but I only tested for the first 30 or 40 shots.. No regulator creep that I can tell. I can let the gun sit for long periods of time and the first shot is always on target.
Noise level is decently low. I wish it was a little lower, but I have not felt it necessary to put a moderator on it and if I do, it will be one I make myself.
Hope this helps.
Oops, forgot to mention 2 other things that needed attention with my Fortitude.
The cheek rest is too low. I fixed this by using a length of foam pipe insulation fitted on the comb to raise it. I secured it with duct tape, but I have seen others have used zip ties to do it. Also, at least on mine, the bolt can swivel to the unlocked position very easily, especially if the gun is inverted. This can cause problems if you fire the gun while the bolt is unlocked like blowing out the breech O-ring, etc. I used a hair rubber band tied to the trigger guard and the bolt. Works perfectly.
Neither of these fixes are what you would call pretty, but they work well and I am only concerned with the utility of the gun, not looks.